The Psychic's Handbook by Green Ronin is an alternative skill and feat based system. It takes some work but ultimately I think it's a better approach to the topic because the powers are open-ended while still being defined within the rules, and the use limitations are fatigue based rather than some silly spell point system. It's easy to learn if you're just introducing it and it's just one short book.
Psionics doesn't use "some silly spell points system"--it's used power points from the very beginning in 1e, so D&D spell point systems are copying from it rather than the reverse.
As far as WotC stuff, the XPH took many steps forwards but some steps back when compared to the 3.0 version (making the psions all int-based and adding the wilder were not good decisions).
I'm going to have to disagree on this one. Having different disciplines based on different abilities is a good idea in theory, but it has two major problems. First, while spellcasters can use any effect from any school equally with a high primary ability (assuming they're not specialist wizards), a psion needs to have high scores in every ability; that's a great balancing mechanism if it were implemented across the board, but if it's just the psion, it makes him too weak relative to others.
Second, in the change to 3.5, boosting ability scores became easier overall, and since casters don't have physical scores as primary abilities, boosting Str, Dex, and Con became easier to boost. Casting, say,
bite of the werebear gives +16 Str; to a Str-based caster, that's a game-breaking boost, and there are many more where that came from.
On the introduction of the wilder, why is that such a bad idea? Wizards have sorcerers, clerics have favored souls, druids have spirit shamans, psions have wilders.
Complete Psionic has a reputation on these boards for being an unbalanced disaster, but I don't have it so I can't comment too much. Fundamentally, it's all basically a variant magic system and has similar balance concerns as the core magic system.
Similar concerns, yes, but it's not nearly as bad as core magic.
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As to my opinions on WotC psionics, PsiH had some great ideas and had a more unique feel but wasn't particularly well-done mechanically; XPH is the most balanced and streamlined psionics system in D&D but relies too heavily on Psionic X powers; CPsi is 1/8 good material, 1/8 broken material, and 3/4 crap. I'll throw in another vote for Hyperconscious and Dreamscarred Press material as well.
In fact, I'd also like to see them use different mental stats, since that's the way it was in 1e as well (your psionic potential and number of PSPs was based on a combination of the three). I'm fairly sure the only reason they didn't do that was that WotC were afraid to try something new, so they stuck with one key ability.
