I forgot to mention the sidebars. The basic class is designed with spell slots and references schools of magic to make it work for anyone. The sidebars for power points, disciplines, and subtle flavor distinctions are to allow those who want to get more traditional with it to do so very easily. My design intent is that the sidebars really are the default--there are playing it closer to how it should be--but placing them as simple variants and sticking with the standard 5e defaults makes it way more accessible to players. Maybe think of the sidebars like feats. They are an optional rule but most games use them.
Okay, on to some specifics.
What about as an addition to the components section, you add in a way for the Psion to skip the required use of components of 100g or more? Even if it's something like for every 100gp value of the component, your constitution drops by 1 to a minimum of 3 for one week, sort of like wish does to strength. It would be a hard sacrifice, but one that could be done by the Psion under his own power if he chooses. The Psion could still opt to use the crystals or whatever if he chooses.
I'm not really sure what to do with high cost components. I like the idea of removing them entirely, and honestly, some of those spells don't really need it. I can't see any particular reason why it would be a problem for a high level psion to just
astral project without extra cost, for instance. Others such as
revivify and
clone do need some sort of significant cost.
Essentially, any solution needs to both:
a) Fit into a sentence or two, and
b) Look like something WotC might have done themselves in a 5e product
B is always the tricky one with fan stuff. We can get so excited making d20 stuff, that we may not realize some of that stuff doesn't really look like 5e. B is a bit priority for me, especially with this psion. This isn't intended to be my ideal psion, it's intended to be the kind of psion I think we could get from WotC.
For this specific mechanic, while the
wish drain precedent seems like the right conceptual idea, I think the granularity is a little too fiddly.
(I was going to come back to this and think of some possibilities, but I need a real life Short Rest, and the post needs posted, so that's for future thought.)
This is a straight refluffed wizard
...
Personally, I don't see much to salvage from the draft as it's a near perfect recreation of the wizard (including arcane recovery and schools of magic, just renamed). If that's what you want, you can get there with just subclass design.
Actually, I expected people to see more similarities with the sorcerer frame than the wizard frame, since in basically all of the places where wizard and sorcerer differ (except in casting stat) it falls closer to the sorcerer side.
Are you of the opinion that sorcerer is basically little different than wizard? (I know a lot of people are, but I don't remember where you stand on that issue.) I recognize that this Psion has a frame that is mechanically very similar to the 5e wizard and sorcerer (it is based on the 3.5e psion, which was in turn very mechanically similar to the 3.5e wizard and sorcerer). Other versions of psions could be made that still capture the essence of the class, but I'm demonstrating that you can make a full caster class that can get the job done with minimal disruption to the 5e rules. I'm also demonstrating that you
can't make an authentic
D&D Psion with a subclass, because all of the core classes do magical stuff that
D&D Psions cannot do. In other words, what I'm trying to say is:
1) Making a
D&D Psion in 5e can't be done with a subclass
3) Making a
D&D Psion full class in 5e can still be relatively easy
On to the class features.
The primary balance points I'm seeing you point out are:
-The class would basically be balanced with wizard without augments, so those are just extra power
-Suppress Display might be too strong in and of itself, and being able to do it automatically at 14th-level is way too strong
-Augments are are better than sorcery points because you don't have to split them with creating spell slots
Yes, balance has not yet been achieved

(Alghough, to be fair, I erred on the side of overpowered for the first draft, just like the UAs do.)
So, let's see what I can do with some of these ideas. I'm mostly going to be sharing my thoughts, maybe some redesign speculations, etc.
I mentioned a bit about the intent of Augment in the other post, but it's mechanically essentially supposed to be the secondary dynamic option--it's the thing they get to decide to do other than just deciding what spell to cast. Thematically, it's where we can extend beyond the real core of the
D&D Psion into the other lesser or less universal features beyond the basic core. So it
needs to be cool! And it need to be
D&D Psion-y. Of course, we don't want the class to end up overpowered, so we need to reign it back to what works.
But first, let's go into the balance of the class against wizard or sorcerer
without Augments. I think sorcerer is easier to compare, but sorcerer it also poorly designed IMO, with too few spells known (unless you're Divine Soul), and a horrible economy of having to give up it's version of Arcane Recovery (ie, Sorcery Points) just to power it's metamagic and some of it's subclass features (plus a couple other problems). Honestly, I don't know if I could even play a 5e sorcerer without house rules, it bothers me so much.
Psion Compared to Wizard
Spell Selection
-Less than half as many spells on class spell list
-Spell selection somewhat inferior quality even if it were the same size
(ie, if you pruned the wizard spell list down to the same size, assuming you kept the good ones, the wizard spell list would be superior)
+Has some condition removal capabilities (and
revivify--which could be ditched)
+Includes all telepathic stuff (could remove some of the ones that have more specific flavor)
-1 to 7 less spells known/prepared daily
-No ritual casting
Spell Power
-No ritual casting (yes, this was in the other category too)
-Wizard gets Spell Mastery (I'm ignoring Signature Spell, because I don't have a capstone to compare yet)
+Equivalent of an extra use of Arcane Recovery (Removed--see below)
Spell Casting Mechanics
+Casts without components (unless certain cost) -- but display makes casting discernible
+Self-buffs have double duration
+Creatures created with
conjure animals and
find familiar immune to being affected by certain spells because of change in creature type
Overall, here's what I'm seeing:
-Wizard is far superior on spell selection. Sorcerer is probably superior overall also, outside of the some specialties like telepathy.
-Spell power is about balanced. To be design conservative, I might say Psion comes out a bit ahead here.
-Psionic spellcasting (manifestation) mechanics is straight up superior. (Which it probably should be, since psionics is superior for monsters in 5e, and has generally been superior in the past also.)
A question is how impactful is the level of superiority of the psionic manifestation mechanics? How often do the three things it has going for it make a substantial difference in play effectiveness?
Even WotC felt that the sorcerers' lack of spell selection justified a whole new feature, so I think it's safe to say that that same lack for the psion should justify more feature space.
As of now, the only thing here that seems like it might benefit from rebalancing would be Psionic Replenishment. I really like the idea of it being something that just happens any time you take a short rest. At the same time, it might be using too much of the class power budget. Originally, I was going to have the Augment Psionic Spell uses handle this--being able to boost your spell was effectively giving you more power power points throughout the day. Then I realized I'd end up with exactly the same mess as sorcery has where it is worse than Arcane Recovery because you have to steal from it to power metamagic. I did
not want to repeat the very design flaw I hate by making getting more power points compete with doing interesting things with them. What I might do is change the value of Psionic Replenishment so that it works on every short rest, but is only half as powerful as Arcane Recovery. That way if you get the normal amount of short rests you regain an equivalent amount, but you can still theoretically regain more power with more rests. For now, let's just say Psionic Replenishment is 1/day, exactly like Arcane Recovery.
With the change to Psionic Replenishment, it looks like the power balance is quite a lot to the wizard side. Unless, "you can't stop me from casting by tying up my hands" is a huge deal in a particular game, there is little draw to playing the psion.
One thing that does need to be determined is if and how one can stop a conscious psion from manifesting powers. I took off the proficient armor issue, because if tying up their hands doesn't stop them, it doesn't seem like sticking a leather jacket on them should either. But maybe maintaining the issue of not being able to cast spells in non-proficient armor would be useful thing. It probably doesn't matter to much either way on that. The more important question is how problematic is it if a
D&D Psion cannot be prevented from manifesting powers while conscious by being bound and gagged? A sorcerer with Subtle Spell can pull off the same thing (with a limited resource), and a
D&D Psion should be better at that.
I'm running low on Power Points myself right now, so I'm going to stick a mental bookmark there and finish this post up.
I'd probably use the Warlock chassis to build a Psion if I weren't making a chassis from scratch. Limited spell slots is fine when you have limited spells to pick from, you can have other abilities as at-will/per day invocations, and you can use the patrons as schools to further flavor different kinds of disciplines.
Hmm, I like that enough to spitball a little more. Three patrons is three subclasses, so maybe Mentalist, Metabolic Warrior, and Elementalist, roughly indexing Mind affecting/clairsentience, body mods/portation, and summoning/force projection. Each comes with some bespoke invocations and spells, and the general invocations cover more general psionic abilities and metapsionics. Generally speaking, lower level abilities across the disciplines could be generally available and the higher powered ones would be 'patron' specific. Huh, I like a fair bit actually.
I still don't really "get" the warlock chassis for a Psion. Although I suppose I snagged its Spell Slots as my Augments. I think it would probably be cool, and
maybe could somehow tap into some of that 2e skill-based feel by using invocations more than spells, but it hasn't crystalized into anything in my head. Maybe it would be an easier base to create something with a 4e feel, where you augment your Invocations? Ki as Power Points has merit too. Maybe some crazy mix of those 2 to get really out there.