Having just read the class description, I agree with you on this, especially in a "psionics = magic" setting. This is actually a class I've been wanting for a while; I already has some semi-complex house rules in place for a wizard that uses power points.
The DM in my session has worked on converting Equestria to d20 settings, and he did exactly that because it would be easier to track power point totals than spell slots, especially for first timers. In such a setting, Twilight Sparkle would have access to multiple disciplines rather than just one as a Psion. She would have to study specific discipline powers by herself, which fits her personality very well.
Some of the spells she pulls off are a bit difficult to explain (Ectoplasmic wings on Rarity, but astral constructs don't last that much long without PrCs), others much easier. (Dimension Slide, Deja Vu, Mindlink, Null Psionics Field against Discord, etc) Manifestation of Elements of Harmony is easier to codify as Metaconcert rather than an epic ritual; in this case Twilight would have manifester level of around 8~9 at S1E02, and 11~12 at S2E02.