My Robots/Dark is currently sitting happily at 39, currently unlikely to get much further until I7 and possibly not then as I feel extremely underwhelmed by the 41-50 villain content. I have played two different builds extensivly and tried another on test a fair bit. Plus knowlege of a lot of the other powers from my other characters.
Level 10: Air Superiority - Don't bother as a mastermind your whole reason in battle is to avoid the notice of the mobs if you start attacking they will notice you and you will die. Far better getting a leadership pool earlier.
On the subject of leadership don't bother with Manuveurs, get assault and tactics, it offers such a low buff you probably won't even notice it.
Tis is what I would go for if looking at the same pools:
01) Battle Drones ->AccAccDmgDmgDmg
01) Twilight Grasp ->AccAccHealHealHealRechg
02) Tar Patch ->RechgRechgRechg
04) Darkest Night ->EndRdxEndRdxEndRdx
06) Equip Robot ->EndRdx
08) Hover ->FlyFlyFly
10) Swift ->Run
12) Protector Bots ->AccEndRdxDmgDmgDmgDisDur
14) Fly ->EndRdxFlyFlyFly
16) Shadow Fall ->EndRdxEndRdxEndRdx
18) Hurdle ->Jump
20) Stamina ->EndModEndModEndMod
22) Assault ->EndRdx
24) Tactics ->EndRdxEndRdxTH_BufTH_BufTH_Buf
26) Assault Bot ->AccDmgDmgDmgDisDurDisDur
28) Petrifying Gaze ->AccAccRechg
30) Fearsome Stare ->AccAccRechg
32) Upgrade Robot ->RechgRechgRechgEndRdx
35) Group Fly ->EndRdxEndRdx
38) Dark Servant ->RechgRechgRechgTH_DeBufTH_DeBufAcc
However Stamina can be taken later, and if you can I would plan to take Recall friend as when going through lifts bots can and do get stuck more frequently than is nice. Being able to recall them is much better than unsummoning and respawning them. Slots are approximate, and again would be how I would slot the build. Shadow fall could do with more slots as could darkest night. I don't normally take Health, it offers a low boost that I find if I have more manuverability I can generally avoid some foes thus not needing the extra regen.
This is my current build:
01) Battle Drones ->AccAccDmgDmgDmg
01) Twilight Grasp ->AccHealHealHealRechg
02) Tar Patch ->RechgRechgRechg
04) Darkest Night ->TH_DeBufTH_DeBufTH_DeBufEndRdxEndRdx
06) Recall Friend ->IntRdx
08) Equip Robot ->EndRdx
10) Assault ->EndRdx
12) Protector Bots ->AccDmgDmgDmgEndRdxDisDur
14) Teleport ->EndRdxRangeRangeRange
16) Shadow Fall ->EndRdxEndRdxEndRdx
18) Tactics ->EndRdxEndRdxTH_BufTH_BufTH_Buf
20) Fearsome Stare ->AccAccRechgRechg
22) Hover ->Fly
24) Swift ->Run
26) Assault Bot ->AccDmgDmgDmgDisDurDisDur
28) Hurdle ->Jump
30) Stamina ->EndModEndModEndMod
32) Upgrade Robot ->RechgRechgRechgEndRdx
35) Petrifying Gaze ->AccRechgRechgHold
38) Dark Servant ->AccRechgRechgRechgImmobImmob
Hover is only in due to lag and TP not doing so well together. Though with that in mind it can be useful in battle with some mobs getting me out of AoE range.
I would definitely go for Fearsome Stare over Repair. You have a very good heal in Twilight Grasp and with Fearsome Stare you will be cutting down the incoming fire a lot! It is one of my favourite /dark powers.
Thanks for opinions, I'll try to skip out manuvuers and go for assault and tactics, after all robots are expendable. And when people finally kill the assault bot, WHAM here comes another one, lol. Anyway the only reason I didn't pick hover and got air superiority instead is that I tend not to use it alot at 20+ and its' good in pvp to keep heroes out of my way. I will change it at some point, and besides, I can jsut respec later on. 
I will try to replace with manuveurs with assault and get tactics later on, that mans at lvl 30 and 32 I can fit in repair and fearsome stare, the ultimate healing build I have. I have my protector bots which buff and repair, twilight grasp and repair for my big chunky assault bot.
If your Twighlight Grasp is not enough to heal the pets they will die to quickly anyway. Plus in PvP heroes will not bother with your pets they will just hit you and kill all the pets in one go.
Repair is good for only one thing and that is to boost a prot bot that has run out of end.
Prot Bots are better specced for damage than for healing as their heals are too random to be relied upoun. (1-2x ACC 3x DMG 1x End RDX - And depending on how may ACC a Disorient duration is useful to extend the disorient from the grenades.)
Plus theAssault Bot is only really dangerous to squisheys or when it has all its upgrades. If I kill it first I would then either have less problems killing the replacement or I'd kill the MM either works fine.
At level 32 you would be better off getting the final upgrade power, while both the hold power and the cone fear power are rather good and give good extra control, if you don't upgrade the pets they won't be able to kill fast enough for you.
If this is to be a PVP specific build I would recommend getting at the very least Stealth and Grant Invis. But Teleport is good too, a well slotted TP Foe can be used to grab enemies and drop them into a pre placed tarpatch. And because the tar patch reduces the resistance of foes your bots can cut through them quickly.
This was pretty much the only way I found of getting easy kills in a zone. (Arena is much harder as you seldom have time to buff before your enemy kills you. 
& Same with Bases Raids)
Well after much consideration I have finalised what I am going to pick for my robo/dark build, but I can't be bothered posting it, or I may do afterwards.
**EDITED**
I decided to post my finalised build;
Level 1: Battle Drones
Level 1: Twilight Grasp
Level 2: Tar Patch
Level 4: Darkest Night
Level 6: Equip Robot
Level 8: Fitness-Swift
Level 10: Flight-Air Superiority
Level 12: Protector Bots
Level 14: Flight-Fly
Level 16: Fitness-Health
Level 18: Leadership-Assault
Level 20: Stamina
Level 22: Shadow Fall
Level 24: Leadership-Tactics
Level 26: Assault Bot
Level 28: Fearsome Stare
Level 30: Repair
Level 32: Upgrade Robot
Level 35: Flight-Group Fly
Level 38: Dark Servant
I'm not ognna change it now, I'm happy the way it is, but if you want to give your opinions then go ahead.
Hi, lately I have been looking at MM threads and have noticed robotics and darm miasma are becoming increasingly popular so I have decided to enrole one myself, I am gonna post my build on what I might do.
Name: Darkness Tech
Archetype: Mastermind
Primary Power Pool: Robotics
Secondary Power Pool: Dark Miasma
Level 1: Battle Drones
Level 1: Twilight Grasp
Level 2: Tar Patch
Level 4: Darkest Night
Level 6: Equip Robot
Level 8: Fitness: swift
Level 10: Air Superiority
Level 12: Protector Bots
Level 14: Fly
Level 16: Fitness: Health
Level 18: Leadership: Manuveurs
Level 20: Stamina
Level 22: Shadow Fall
Level 24: Leadership: Assault
Level 26: Assault Bot
Level 28: Leadership: Tactics
Level 30: Repair OR Fearsome Stare
Level 32: Upgrade Robot
Level 35: Flight: Group Fly
Level 38: Dark Servant
I had a real time trying to pick what powers to get and when, since I had 3 other pool powers. Could you please comment on my build and if so you can post your own recommended builds. Your criticism (good or bad) is appreciated, thank you.