Here's a list of some of the Pros and Cons of psionics, in my opinion, to the extent that they apply to Patria.

Good Balance,
Helps cover some archetypes (PsyWar as a monk alternative, creepy little girl who blows stuff up with her mind as a psion, etc.)
Very, very good system, with augmenting being a solid plus. Intuitive, too.
Can be fairly easily refluffed.
Fun? That's about it.

Psion is fairly high-powered, although maybe not more so than the Mage classes. Definite Tier 1/2.
Highish-magic/fantasy. Seriously, crystals as a major structural component? leaping through time? Eating brains? Having a pet crystal with little spindly legs that thinks for you? Creating demiplanes? All noes. You'll notice that I removed all the similar wizard spells while making the Mages.
Very much not in keeping with the flavor, to use the default fluff. Too much astral plane, time-screwing, body-trading nonsense.

Final Notes: System is good, fluff is not. But I don't want to refluff it... already did that with countless vestiges, and the mages. I'm pretty much tired of changing fluff around to salvage a workable system.

I might just make a banlist of powers, classes, etc and try to make some sweeping refluffs (dorjes are now able to be made of any material, not just crystal, etc.)