Repeating myself? I've thought about this more.
I don't want something as complex as 3.x.
I want a class that can upscale things, by consuming their own lifeforce (hit die?). Possibly crystals or something else, but not a defiler (though maybe this is the chassis for that?).
I want one subclass that manipulates space and time.
One subclass that is all about using force to move things.
One subclass that controls others (even if only for an action or so).
I thought I wanted a subclass that has complete control over its own body, but that might be monk. OTOH, one that really goes all in on the weird creepy tentacle stuff and reshapes their own body? I'm for that.
abilities that allow for astral projection or other stuff like that? Yes please.
I've come around to the "just another spellcaster" being the only way we are getting psionics (though some of this really should be things they can do). What I want is the FLAVOR of the old psionic classes. With some abilities, some spells, some way to scale those spells.
I think Wizards, sorcerers, and psions suffer from their ability to do almost everything the other can do. If we had more restrictions on spells, and more emphasis on other things they can do, we'd get better distinction among the classes even if they largely are similar with spell slots.
I don't think the current version is even near perfect, but I think it's a good start - 1E psionic and 2E psionicist characters were practically spellcasters in all but name, just with a different resource management in manifesting/activating, relying on PSPs instead of Spell Slots, and the whole idea of power checks was from 2E, with 1E power activation just working if you could pay the points, and then either requiring a saving throw, or with attack/defense mode combat, a percent chance of success (basically a different kind of saving throw). 3E was more transparent in powers being analogous to spells, and 3.5 even more so. Complexity was always inherent in psionics, especially with 1E and 2E. 2E Psionicists could know up to 35 powers at level 20 - 2025 Psion caps out at 22 Spells, not counting any granted by their subclass, and 5E offers scalability on quite a few spells available to the new Psion.
It's definitely been much tougher to differentiate between Wizards, Psions, and Sorcerers, separate from all the other casters, because they have other clear abilities and niches that really highlight them - Warlocks have pact magic, pact abilities, and invocations, Druids have wild shape, bards have inspiration and their other bardic abilities, and so on. Sorcerers sort of have their niche abilities with sorcery points and subclasses, wizards are more defined by their reliance on spells and flexibilities in selecting them, and psions have an opportunity to carve their own niche with psi dice (less a mouthful than psionic energy dice, if the can abbreviate it), and subclass features based on disciplines. 3E pushed the scalability of psions by doing new psionic analogs of spells - half the time, they just pasted psionic in the front of the name, but a few times they did something new - Psionic Charm, for example, allowed higher point expenditure for more advanced versions of the charm spell (one power covered Charm Person, Charm Monster, Etc) - though 5E has done that with some spells (like Cure Wounds), others like Charm Person have multiple versions based on level - to make the Psion uniquely flexible, they could return to those roots and do scalable spells like Psionic Charm for the Psion List to allow some flexibility. Another thing to remove complexity and differentiate them from most casters could be to use the Warlock's spell slot advancement and short rest recovery (to emulate the faster power recuperation of 2E, for example), and maybe do devotion/science powers in place of invocations, for example?
