I posted comments on the following topics during the round one playtest:
1. Intimidate should be a class skill for all Vigilantes. The reaction here was overwhelming and it was an easy fix. Probably just an oversight in the first place. Either way, 100% satisfied.
2. Warlocks should have some ability to cast in armor. The Caster's Defense talent takes care of this nicely, and doesn't feel like too much of a 'tax' since Combat Casting is an ability that an armored warlock would probably want anyway.
3. Silent Dispatch sets a terrible, terrible, rules precedent. We debated extensively whether or not a stealthy one-shot take down was 'combat' (and hence DC -10 to hear). Then someone pointed out that the description of the Perception skill doesn't mention 'combat', it says "Hear the sound of battle" and I don't think anyone would consider a stealthy takedown to be 'battle'. In any case, I'm actually not too worried: I talked this over with my group and we unanimously agreed to throw out this rule if it made the final cut.
4. Various issues with Mystic Bolt. The rules clarification is very welcome. Now that it functions like a light weapon that rapidly pops in and out of existence, it is much easier to tell which feats/modifiers apply to it an which one's don't.
Now only one two major issues remain:
By limiting it to a single damage type (and the warlock certainly does NOT have spare talents to take Mystic Bolt multiple times) the ability becomes useless depressingly often. Especially as the Vigilante starts building a reputation ("And remember, the Caustic Avenger is patrolling the streets, so keep your potions of Protection From Acid handy.") The damage should either be untyped, or they should be able to swap damage types at will.
The damage still seems low (and actually had its bonus damage nerfed 75% between the 1st and 2nd playtest). If you could use Power Attack or Deadly Aim with it, that would be one thing (but it's a light weapon and a touch attack, so those options are out). Being able to get the Vigilante's dex or int bonus to damage would work as well (is there is some way to do this that I've missed?). Arcane Striker is something, but 2d6+6 (1d6+3 base, +3 arcane strike, +1d6 arcane striker) at 12th level is pretty darn weak. Those touch attacks will probably hit, but unlike weapon attacks you still need to worry about SR.