I see your point. He would run out of PP fast if he tries to use it every encounter. What about making it activated by swift action and lasts 10 rounds, letting you use it once per round? That way, you'd only need to activate it once or twice per encounter, so your PP isn't drained quite so quickly.
Edit: Okay, I've removed the 1/2 manifester level clause and changed Psychic Strike, is this reasonable, OP, or still weak?
Looks good. Now he gets a reasonable amount of damage for those PP while at the same time having enough left to think about what powers best supplement it. I would play this class in preference of the regular soulknife.
Also, the first thing I thought when I saw the new pic was "Now that's what the xephs should have looked like."