Do you really need ALL those acc enhancements?
UNION @Flitz 50, Lead Hose 50, Red Rag 50
DEFIANT Rose Bloodthorn 34
VIGILANCE Captain Caledonia 20 - Yeah, I made toons on the French server coz we only had 4 back then (might have to transfer/recreate them on one of the US servers)
..and many more!
- Drop one +Acc from each of your summons, and redirect them into 1x Rchg and 2x Heal for Triage Beacon as it doesn't shine without a boot up the posterior.
- Drop 2x Rchg from Equip as it recharges fast enough on its own. Move one to Tactical Upgrade, and the other to Triage.
- You have very little in the way of attack powers and toggles (2x Leadership) so I can't see why you bothered with Stamina, depriving you of other power choices. Consider Aid Other for keep your Mercs alive along with your Medic (Slot 1x Rchg, 2x Heal).
- Consider switching Spec Ops Acc x2 to Dam x2 as Tactics should take care of your accuracy needs.
- Consider dropping 1 or 2 Acc from Trip Mine and replace with Rchg
It's a solid build, and no doubt tweaked for your playstyle, but have a look at the above suggestions and see if any click with you...
If it were me, I'd drop Seeker drones.
I've seen quite enough of their AI in action with my Protector Bots and frankly they're not worth taking. (Caveat: I've not actually taken the power itself on Toybox, as I was massively put off by my experience via the bots, other peoples experience may vary 
)
You may want to take TP Foe instead, so that when you get trip mine, you can drop a Tm, and a poison trap, then..........
Warning:
The above post may contain Cynicism, sarcasm and/or pessimism. If you object to the quantities contained, then tough.
Ditto on Seeker Drones. Normal pets do tend to wander off and aggro things by accident. Drones are EXPRESSLY DESIGNED to do this, so it's not a bright idea.
Of more surprise to me is the Fitness set - MMs are one of the few classes that don't need it, providing you put EndReds in any constant drain powers like Leadership. So that's three other powers you could be picking...
Really surprised that you hate Acid Mortar as well - with SOs it's a significant help to your pets, and also tends to be a valuable aggro magnet to keep nasties off you...
Is it time for the dance of joy yet?
Alrightey, thanks for the advice so far guys. I'll tweak the build then post it up when it's done.
However, to address a couple of things:
Fitness. I know this isn't vital, per se, but I have a very proactive approach with my Mastermind in combat; namely as the Minions and other team members have tied the enemy up, and have their aggro, I'll be nipping in the back slapping down traps, caltrops....etc all over the place. This can quickly add up in terms of Endurance, heh. Another reason I took Fitness is the endurance cost when it comes to equipping and upgrading the Mercs; it adds up, and I hate slowing everyone down by running on empty half the time.
If anyone can suggest ways I could overcome this, that'd be hugely appreciated.
As for Seeker Drones....
Well, the original reason I took them was for a little extra assurance when it came to nullifying alpha strikes. Summon the Drones on top of the enemy, and not only do they get the aggro for a moment - giving everyone else time to launch a volley - but when they explode, they always seem to annihilate the mobs' chance of hitting anything with their counter-attacks.
This might just be me, however, so there's still plenty of time to convince me out of taking them. If I do get rid of them, I'll replace them with Acid Mortar going by the advice above. 
To my mind in beta I never found it worth taking up three powers (Swift/Hurdle, Health, Stamina) to just get a little more endurance during the summoning and buffing stages, whih I can get an Endurance Inspiration or two for free and have that do the same job.
Of course, if you feel you benefit from the selection more than you would than additional powers and abilities then fair play to you!
I'm also quite active in combat - Bubbling, Blasting and Force Bolting but when I was high-level in beta I still felt no need for Stamina. YMMV though.
Seeker Drones I liked, even from Protector Bots - as you say they're a nice aggro soak, and have some nice effects. I just think they're much maligned! (and more useful when you choose the summon point and not a Prot Bot).
Aid Other, Acid Mortar and another random power would be my suggestion for replacing fitness - perhaps Detonator since if a henchman is going to die he might as well go out in a blaze of glory!
Hmm, good points; guess you've kinda nailed it for me there.
I'll tinker with things, coming up with something I feel is decent, then post it again.
Ok, here we go. Version two of the build.
---------------------------------------------
Exported from Ver: 1.7.5.0 of the CoH_CoV Character Builder
---------------------------------------------
Name:
Level: 41
Archetype: Mastermind
Primary: Mercenaries
Secondary: Traps
---------------------------------------------
01) --> Soldiers==> Dmg(1)Dmg(3)Dmg(3)Acc(5)Acc(5)
01) --> Web Grenade==> Acc(1)
02) --> Caltrops==> Slow(2)
04) --> Triage Beacon==> Rechg(4)Heal(7)Heal(7)
06) --> Equip Mercenary==> Rechg(6)EndRdx(9)
08) --> Hasten==> Rechg(8)Rechg(9)Rechg(11)
10) --> Acid Mortar==> DefDeBuf(10)DefDeBuf(11)DefDeBuf(13)Acc(13)Acc(15)
12) --> Spec Ops==> Hold(12)Hold(15)Hold(17)TH_DeBuf(17)TH_DeBuf(19)TH_DeBuf(19)
14) --> Super Speed==> Run(14)
16) --> Force Field Generator==> DefBuf(16)DefBuf(21)DefBuf(21)
18) --> Aid Other==> Rechg(18)Heal(23)Heal(23)
20) --> Poison Trap==> Slow(20)Slow(25)Slow(25)Hold(27)Hold(27)Hold(29)
22) --> Assault==> EndRdx(22)
24) --> Tactics==> TH_Buf(24)TH_Buf(29)TH_Buf(31)EndRdx(31)
26) --> Commando==> Dmg(26)Dmg(31)Dmg(33)Acc(33)Acc(33)
28) --> Seeker Drones==> TH_DeBuf(28)TH_DeBuf(34)TH_DeBuf(34)Acc(34)Acc(36)
30) --> Hover==> Fly(30)
32) --> Tactical Upgrade==> Rechg(32)Rechg(36)Rechg(36)Rechg(37)EndRdx(37)
35) --> Trip Mine==> Dmg(35)Dmg(37)Dmg(39)Acc(39)Acc(39)Rechg(40)
38) --> Serum==> Rechg(38)Rechg(40)Rechg(40)
---------------------------------------------
01) --> Sprint==> Empty(1)
01) --> Brawl==> Empty(1)
01) --> Supremacy==> Empty(1)
02) --> Rest==> Empty(2)
---------------------------------------------
Couldn't bring myself to ditch Seeker Drones, no matter how much I tried.
I was originally going to add the two damage SOs to Spec-Ops, but then I realised: If they're tossing out tear gas and flash bangs like there's no tommorow, why not fully slot out those capabilities? As a result, I've enhanced their hold and ToHit Debuffs above everything else.
Guess what? More suggestions
- A fourth recharge in TacUpg? Negligible benefit, drop it and move it to Web Grenade as an Accuracy or Aid Other as a Heal
- Drop the extra Acc from Commando - he cons higher than you and has your Tactics. Move it to Hover as a Fly.
- Consider changing one ToHit Debuff or one Hold on Spec Ops to an Acc as they'll do no good if they can't hit regular (they only need the one because of Tactics)
- Consider changing one Slow and one Hold on Poison Trap to Acc's as they do no good if they can't hit regularly.
- Consider dropping the End Rdx from TacUpg (it takes long enough to recharge anyway that you should have most of the End back) and move it to Soldiers as a Heal. It'll buff your Medic a bit.
Otherwise, I reckon this version of the build is showing some good new utility, and is equally sturdy (note I'm down to enhancement suggestions!). Pack a couple of blue candies for setup, and you'll be good to go.
And I'm done.
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Exported from Ver: 1.7.5.0 of the CoH_CoV Character Builder
---------------------------------------------
Name: Eressos
Level: 41
Archetype: Mastermind
Primary: Mercenaries
Secondary: Traps
---------------------------------------------
01) --> Soldiers==> Dmg(1)Dmg(3)Dmg(3)Acc(5)Acc(5)
01) --> Web Grenade==> Acc(1)
02) --> Caltrops==> Slow(2)
04) --> Triage Beacon==> Rechg(4)Heal(7)Heal(7)Heal(33)
06) --> Equip Mercenary==> Rechg(6)EndRdx(9)
08) --> Hasten==> Rechg(8)Rechg(9)Rechg(11)
10) --> Acid Mortar==> DefDeBuf(10)DefDeBuf(11)DefDeBuf(13)Acc(13)Acc(15)
12) --> Spec Ops==> Hold(12)Hold(15)Hold(17)TH_DeBuf(17)TH_DeBuf(19)Acc(19)
14) --> Super Speed==> Run(14)
16) --> Force Field Generator==> DefBuf(16)DefBuf(21)DefBuf(21)
18) --> Aid Other==> Rechg(18)Heal(23)Heal(23)Heal(37)
20) --> Poison Trap==> Slow(20)Slow(25)Slow(25)Hold(27)Hold(27)Hold(29)
22) --> Assault==> EndRdx(22)
24) --> Tactics==> TH_Buf(24)TH_Buf(29)TH_Buf(31)EndRdx(31)
26) --> Commando==> Dmg(26)Dmg(31)Dmg(33)Acc(33)
28) --> Seeker Drones==> TH_DeBuf(28)TH_DeBuf(34)TH_DeBuf(34)Acc(34)Acc(36)
30) --> Hover==> Fly(30)Fly(37)
32) --> Tactical Upgrade==> Rechg(32)Rechg(36)Rechg(36)
35) --> Trip Mine==> Dmg(35)Dmg(37)Dmg(39)Acc(39)Acc(39)Rechg(40)
38) --> Serum==> Rechg(38)Rechg(40)Rechg(40)
---------------------------------------------
01) --> Sprint==> Empty(1)
01) --> Brawl==> Empty(1)
01) --> Supremacy==> Empty(1)
02) --> Rest==> Empty(2)
---------------------------------------------
I would slot Poison Trap with Accuracy SOs, but it doesn't take them.
Well, I wouldn't want to meet that platoon in Warburg
I have to say, this build works beautifully and I'd heartily reccomend it to anyone. o.o
While I'm not hitting everything all the time, the sheer effectiveness of the squad is incredible. The Acid Mortar more than makes up for the loss of Accuracy SOs against Bosses (In retrospect, AM only underperformed BECAUSE I was jacked up with SOs), Triage Beacon is....well, Triage Beacon and Aid Other is a damn sight more useful than I thought it'd be (Healing around 400 HP a pop).
In addition, the new arrangment of slots means my Spec-Ops can keep an entire group locked down as I move in with the mines, and the other squad members open fire. It's wonderful.
[sniff]
Just hit 38, so haven't had a chance to really test out Serum, but I'll probably be singing it's praises soon enough.
Alright, as I'm rapidly approaching level 40, I've decided to arrange the second respec trial within the next few days. It's with that I'll be perfecting my build up to level 37 - my current level - as well as fleshing out those final few key moments. So here it is, my build:
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Exported from Ver: 1.7.5.0 of the CoH_CoV Character Builder
---------------------------------------------
Name:
Level: 41
Archetype: Mastermind
Primary: Mercenaries
Secondary: Traps
---------------------------------------------
01) --> Soldiers
- Damage(1)
- Damage(3)
- Damage(3)
- Accuracy(5)
- Accuracy(5)
- Accuracy(7)
01) --> Web Grenade- Accuracy(1)
- Accuracy(40)
02) --> Caltrops- Slow(2)
- Slow(19)
04) --> Triage Beacon- Healing(4)
06) --> Equip Mercenary- Recharge Reduction(6)
- Recharge Reduction(7)
- Recharge Reduction(9)
- End Reduction(9)
08) --> Hasten- Recharge Reduction(8)
- Recharge Reduction(11)
- Recharge Reduction(11)
10) --> Swift- Run Speed(10)
12) --> Spec Ops- To Hit DeBuff(12)
- To Hit DeBuff(13)
- Hold Duration(13)
- Hold Duration(15)
- Accuracy(15)
- Accuracy(17)
14) --> Super Speed- Run Speed(14)
16) --> Force Field Generator- Defense Buff(16)
- Defense Buff(17)
- Defense Buff(19)
18) --> Hurdle- Jump(18)
20) --> Stamina- Endurance Modification(20)
- Endurance Modification(21)
- Endurance Modification(21)
22) --> Poison Trap- Hold Duration(22)
- Hold Duration(23)
- Hold Duration(23)
- Slow(25)
- Slow(25)
- Slow(27)
24) --> Assault- End Reduction(24)
26) --> Commando- Damage(26)
- Damage(27)
- Damage(29)
- Accuracy(29)
- Accuracy(31)
- Accuracy(31)
28) --> Seeker Drones- To Hit DeBuff(28)
- To Hit DeBuff(34)
- To Hit DeBuff(34)
- Accuracy(36)
- Accuracy(36)
- Accuracy(36)
30) --> Tactics- To Hit Buff(30)
- To Hit Buff(31)
- To Hit Buff(34)
- End Reduction(39)
32) --> Tactical Upgrade- Recharge Reduction(33)
- Recharge Reduction(33)
- End Reduction(33)
35) --> Trip Mine- Damage(35)
- Damage(37)
- Damage(37)
- Accuracy(37)
- Accuracy(39)
- Accuracy(39)
38) --> Hover- Flight Speed(38)
- Flight Speed(40)
- Flight Speed(40)
---------------------------------------------01) --> Sprint
- Run Speed(1)
01) --> Brawl- Accuracy(1)
01) --> Supremacy- Empty Enhancement(1)
02) --> Rest- Recharge Reduction(2)
---------------------------------------------A few comments:
I've skipped Acid Mortar because, in my experience, it wasn't worth the power selection and slots for my Mercs. The DefDeBuff isn't really noticed, as my Mercs hit all the time anyway, and the -res - while nice - isn't enhanceable, and I've done without it for this long.
I skipped Detonator because, to me, sacrificing sustainable damage for a quick burst isn't worth the loss of a unit, the activation time or the luck involved. If I was using Zombies or Robots, I would probably have taken this.
I've taken Hover because I needed something to get over the lack of vertical travel I have.
So....any comments or criticism?