Dont know majority of answers but I get the ball rolling.
3) Pretty much yes. Most hero teams will spot you without it but it can be good practise. I dont know about defiant but there are stalker hunters on union. They can see me with my stacked stealth (have to be in a close proximity) but can still get them if quick enough.
4) I say its a good set. The entropy shield can be nice and handy (prevents you being teleported). The only one that can heal (afaik) is regeneration.
6) That is correct. By collecting 6k bounty in sirens call you get a single origin of your choice which is +3 to your level. Its how I got most of my enhancements 
7) I suppose this really depends on the person and the AT. I myself have it on ruthless. I can solo but much prefer teaming.
8) Well im union based so dont know this answer either. However you really dont need a stalker orientated sg. Im sure anyone would really do with just a couple of stalkers in it (most would have afew in an average size sg) so you can ask afew questions etc.
The only thing about stalkers is I found them quite slow to level early on as seemed abit weak. This is when teaming with your sg (or whoever) will help. Once you have gained afew levels and have afew of the must have powers such as Hide, AS, Placate etc you be a killing machine.
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here's my 2 cents...
1) Sorry havent got a clue 
2) I too like the anim for barrage, yep is does do less damage than energy punch, but then it also has a quicker recharge, tbh the only time your gonna use it out of hide is in outbreak if you take it over energy punch, but wether it's worth taking depends on how you want to play a stalker and what secondary you decide to take. (If your going down the EM/EA route the I would'nt take it, stalker builds are tight enough as it is).
3) Stealth is essential if you intend on doing PVP, against PVE there's not really any need for it.
4) EA again depends on How much PVP your gonna do, I only have Kinetic and entropy shields in my build, and I only have Kinetic as I have no choice in the matter (even slotted with 3 SOs at around lvl 30 it will only give approx 11-12% resists without SO's it give 7.5% pretty weak IMHO.
Whereas Entropy Shield is a godsend, gives a nice range of protections and more importantly stops TP Foe in PVP 
5) Repultion, again down to play style, with no heals at all in EA you pretty much gonna be forced into hit and run tactics as you just dont have the HP's or the healing power to scrap, also EM's attacks are quite on the slow side, but then they do the best damage out of all the stalkers.
6) YES !!! 6000 bounty will get you a +3 SO of your choice, but you need to cash it in before you leave sirens call or you will loose it.
7)Definatly with EM/EA you can solo relentless missions with relative ease from lvl 12 onwards providing you take placate at lvl 12.
8) As max says soz were on union, so cant help there.
A few more little points, as a rule i've always pretty much solo'd all my stalkers, If you want to scrap and mainly want to do PVE then EM/regen would be a good choice, even with my claws/regen stalker I can stand toe to toe and scrap bosses on relentless.
Travel powers - for levelling Superspeed is awesome, (some people dont like the ascpect of no vertical movement, but it worked fine for me), it gives you the ability to really rake in xp on relentless if you concentrate on just the mission objectives (avoiding kidnap missions), but for PVP I use Combat Jumping (3x Jump SO's) and hurdle (3x Jump SO's) and Teleport,this gives you a mini super-jump and also has the added benefit that neither are supressed in PVP, a nice advantage that fits in with hit and run tactics.
If you plan to use the above travel power method, i'd recommend getting stamina as well, TP eats endurance, and if your running kinetic and entropy you will have end issues, until you get enery drain at lvl 28, but i love the fact i can escape and it has very little affect on my endurance.
At the moment its a toss up between Energy Aura or Ninjitsu.
I just have a pit in the bottom of my stomach that the Ninjitsu heal will come in handy and save me many times..
But then again no KnockBack/Down protection... Unless I take acrobatics, in which case I would loose Air Sup' and take CJ/SJ/AB. Which I suppose is not as bad a trade as it could have been. That little more defense is always helpfull and I would be more manouverable in battle. Thats great for stalker right?
Yeah I am thinking I will pick up stealth just to be on the safest side of safe. Again the extra DEF is handy.
If I go down the above route stamina is a must at level 20 then. Which is ok by me tbh.
I know the logical thing would be too go /Regen but I have used Regen since I3 and its getting a tad boring always knowing when to take what and use what.
Ah blimey but If I went Regen I could get SS and hence ghost things..
This is a really hard choice..
Any ideas?
K
Tbh as long as you dont mind hit an run's then EM/EA would be a good choice, SS+stealh will give you invisibilty and the ability to get to the mish objective quickly, then when you get to the boss (most relentles mish's will have a +2 boss with either a +2 or +3 minion close by).
Then it's basically kill minion, placate boss, wait for recharge, build up+AS, couple of other attacks (depending on how much the boss hurts you), placate, one more recharge and the boss is dead, mish time start to finish usually 5-8 minutes
I did notice however that as you hit 28-29, and you started getting lvl 30+ bosses they can hit really hard, especially the Tsoo and council, to the point that I occationally got killed in 1 shot, wasnt too bad as any debt soon dissapears on relentless.
The late 20's are always hard..
Yes, I think I will go Em/Ea. I can always just roll again if I find I dislike it.
Anyways cheers for help, have been searching for the answers to the unkown questions all day still cant find anything.
K
SS + Stealth to ghost missions? You have hide, you can ghost all day long without either of those, Rikti drones still see you tho. I have SJ and can hop to the boss/glowie in seconds. I'm also EA, and I gotta tell you I really wish I had a heal sometimes, I could take medicine, but would need to drop stealth or hasten to get it. Decisions decisions.
Ok so maybe then an EM/NJ build with CJ-SJ-AB, its a few toggles aye but with -Endurance costs I'll be ok. And If I also take Hurdle stacked with CJ thats some rapid movement in a fight.
This way get a heal status protection and a few power toys.
Hmmm.. I need to write up a build.
K
I think I can help you with your unanswered question:
[ QUOTE ]
1. What is the Stalker damage cap?
[/ QUOTE ]
I've read it is the same as most of the other archetypes. I think the only classes that get higher than the usual 400% cap are Blasters (500% iirc) and Brutes (was 850%, but there were some rumours it was lowered - all I know is that with full Fury, Build-Up and Fiery Embrace my damage will still increase if I get Forged by a /Therm corruptor).
Ta for the replies.
I've only got to level 6 at the mo' but even now I can see the potential. Just have to get through the lowbie levels and get some good enhances in some powers. I am using red 2+'s at the moment tee-hee.
K
As many of you will know I am rolling a Stalker as soon as CoV arrives. Yet I still have a few issues involving powers etc.
1. What is the Stalker damage cap?
2. Barrage, I like this power. Its animation is brilliant to me. I read one guide which apart from saying its rubbish etc, tried to tell me that the main reason not to take this power was because its damage in hide is lower than that of Energy punch. But why on earth would you use Barrage in hide when you have AS etc?
3. Hide is stealth needed? I will be doing some PvP so, if it gives me that extra chance not to be spotted then I am all for it.
4. EA, good set bad set? The status protection at level 10 is a pretty great feature. Yet it lacks an heal and other utility powers of the other sets.
5. Repulsion, said by some to be a rubbish power, to me though the ability to say "I dont want to fight you now, go away" is a pretty good one?
6. Slightly OT but I heard somewere that SO's are set as a reward in SC. Now this is a very atractive propersition to me, as this is my first time in CoV I'll be short on Infamy.
7. What about mission difficulty, imo a stalker would excel in a 1 red mob 1 orange mob situation that I used too see in Invincible on CoH. Is this plausible however?
8. Any stalker orrientated SG's on CoV Defiant server? To provide a bit of support in my early levels.
Server subject to conformation.
K