Alright, I'm a little late on this dealy, but heres my 2cp on the concept, spoilered so it doesn't break whatever track you guys are on right now
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I had this idea that was essentially, psionics augment with recharge.
Basically, you have three pools of points, the first pool refills every round, the second each encounter, and the third per day. Now, while this is awfully similar to 4e's system,
I figure you could simply design all the 'root' spells such that they should require the most of the 'per round' pool to cast to their level appropriate effect, with the second pool offering access to a different list of augmentation options(encounter changing, or canceling said encounter changing effects, potent defenses), and the third yet another(save or die effects, reversals of such, particularly defenses that are proof against pretty much anything level appropriate(for the round of course)).
Add to this, a means of dealing with extended duration effects, these effects simply cost points appropriate to their duration, to produce an effect that lasts from rounds to minutes requires Encounter points, to produce one that lasts a day requires Daily points, per round points can't have durations beyond 1d4 rounds or instantaneous(that is to say, creating an unsustained magical effect), as a design guideline. And for semi permanent effects, such as Mage Armor, etc, these hog the their allotment from the Daily points until dismissed or dispelled. If you wish to abolish magic item christmas trees, just have it so that these items also take their allotment out of your points, you can only fuel so many(barring Artifacts, which are well, plot devices and hardly for sale).
To put it another way, the first pool might fuel an xd4 shocking grasp, but augmented with the second pool, the shocking grasp now adds a -1/5 augment points penalty to the target's AC for 1d4 rounds as well and with the third, the third might daze, stun or even kill the target.
Likewise, a Shield spell provides the appropriate AC/save bonus for a round as an immediate action, when powered by the first pool. When augmented with the second pool, it then lasts more rounds, adds a bonus to saves and/or adds energy resistance. When augmented with the third pool, it becomes a Fire Shield effect on top of whatever else the augments bought.
Cures heal the damage with the first pool, add temporary hit points or removes lesser debuffs(e.g fatigue) with the second and revivify is a rather expensive use of the third.
Point expenditure is capped by the sum of the character levels, or derivatives of that, while pool sizes are dependent upon power sources(arcane, divine, mental, etc) of the particular class levels(or ToB's class + 1/2 others) and an ability score(which I may note, should be distinct from the attack roll ability score for any particular class). This allows most characters to function just fine with multiclassing, though they'd have less stamina with a particular aspect, and a reduced access to new powers and effects. I'd personally have preferred a universalised power point pool, but so far it seems most people I asked prefer differentiation from the various 'fuel tanks'.
Those with larger pools would be more able to split their efforts between active defenses, utils and offense, while offensive effects(battlefield control, buffing, debuffing and summoning counted here) are inherently limited by hogging the standard or full round actions, swifts and frees should be primarily defensive in nature(active defensive spells, de-debuffing(aka healing)), with movement(teleportation, whatever utility effects) taking the move actions.
What spells/powers are available for these points to be spent on, however, depends upon the particular classes. Certain classes may provide augmentation option access automatically with level, though with fewer unique base powers than classes which require you to buy options.
I'd also like to see a non-compulsory, but effective equipment foci for them, well, that or give the nonmagicals some candy with their own 'spell' access, by sinking their pools into equipment powering(disclaimer, this works better if all classes shared a universal point pool). Flaming sword? Sure, just sink your /encounter pool into it for a one round flaming attack. Doing the same thing with a caster and fireball wands works too.
Restricting access to certain spell types(delaying their accessibility a couple o levels) or reducing their point efficiency, while not making them exclusive entirely, should be the way to go with availability.
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