Bonus feats certainly help. He should definitely be bumped up to a full BAB, though, at a bare minimum. Maybe add lurk/psionic rogue-progression manifesting, but from the psionic warrior list. The first two might or might not push it up a tier, but the latter certainly would.
If you want an "official" fix, the Pathfinder version is pretty good. Better enhancement progression, recharge psychic strike as a swift+psionic focus action, and a whole bunch of snazzy "blade skills." Should be easy enough to back-convert.
I forgot full BAB. My bad, good catch!
As for the PF soulknife, I guess that's an easily available option for anyone who wants