Scars Unseen
Hero
The "same as every caster class" is a point I will directly challenge. Why must psions be casters in the first place? The D&D monk is as close a fantasy analogue to some fictional users of psychic powers as any of the caster classes. The assumption here seems to be that a psion will necessarily be emulating the function of a wizard or similar class, but that is only necessarily true insofar as D&D magic encompasses every role possible due to spell list bloat over the decades.Give the psion the spells that feel thematically appropriate. Same than with every caster class. You don't need to invent an entire parallel magic system for that, any more than you would need to invent a parallel combat system to include laser guns.
My core point has been and remains that the class shouldn't be designed with the assumptions of other classes by default. Rather, the goals of what the class is meant to achieve should be considered first and foremost, with class design following as a result. Psion = science magic user is one possible outcome (and one of the options in the poll), but it is, in my opinion, both the laziest and least satisfying one.