Baaah. I disagree that spell slots and Vancian-esque casting is complicated for newbies. It involves less/smaller math too. I've never known a single new D&Der, not even myself, to have had any problem understanding the concept of spell slots for casters. I also don't see the reason for peoples' hate of the arcane/divine divide; I don't know where it's ever been a problem area or made no sense; the gods work in mysterious ways! Hermetic mages do not!
MP systems may be what console and computer games use for simplicity's sake, but that doesn't mean they're better than D&D's style of slot-based magic. I'd prefer D&D magic be made a bit more Vancian rather than less, if we had to choose. I don't want the Indistinguishable 25th Generic Video Game To Tabletop RPG, I want D&D.
Really all you might need for cutting down on the gads of spell slots a high-level caster has, would be to change how many are received. Instead of X 0-level slots, Y 1st-level slots, Z 2nd-level slots, etc., you'd have A primary slots, B secondary slots, C tertiary slots, and maybe D auxillery slots, or whatever. Your caster level in any given class would dictate your number of slots with that class, and how they're divided up. So a wizard of anywhere from 10th to 20th level would probably have the same number of slots and in the same configuration; 4 primary, 4 secondary, 4 tertiary, and 4 auxillery (or not). They'd prepare 16 (or 12) spells per day; 4 of their highest available level, 4 of their next-highest, and 4 lower-level spells (or 4 of the next-next-highest and 4 lower-level). At low levels they'd only have primary and secondary slots (for 1st and 0-level spells); once they gain access to 2nd or 3rd-level spells, they'd get tertiary slots; then once they gain access to some other levels, either 3rd, 4th, or 5th, they'd gain some auxillery slots perhaps.
......of course, I still want Psionics to be in the 4th edition core rules, as a distinctly different system from the magic system. But then, I want it to more closely resemble 2nd Edition psionics with better balance and more refined rules (probably 3-4 tiers of psionic power rather than just devotions and sciences); and made to work easily enough with various flavors of psionic description, be they Eberronic dreamscape-related powers, pseudo-Eastern philosophic manifestations, or psuedo-scientific powers derived from the mind and body alone. I want the book to include two or three different names for each power and discipline, to represent the breadth of philosophies that can give rise to psionics among different cultures, so people don't get misled by thinking it's purely a psuedo-science thing and doesn't belong in their fantasy game.
(.....Of course, I'd like to see magic spells get a similar treatment name-wise, getting at least second set of names representing a more Eastern style of magic, to support Oriental Adventures material being released later and without the bull**** from folks about "OA isn't core! OA sucks! I don't want your ninjas and monks and cr** in my D&D! You suck for liking OA in D&D, and should feel bad!")
And I want power points to be called Psionic Strength Points again. We already have a term that uses PP as its short-hand, platinum pieces, and I'd rather not abbreviate something as 'pp' anyway. And I want psionic powers to require maintenance costs again darnit, just cuz I do and they make sense (since psi isn't magic and wouldn't operate on magic's funky laws that make spells last so long at no extra cost from the caster).
I vastly dislike 3.5's changes to psionics that make it just a wierd and stupid variant magic, with absurd crystal fetishes and powers-that-duplicate-magic-spells-that-really-shouldn't-ever-be-doable-with-psionics. Crystals only fit with psionics as a convenient storage/focusing medium! They should not be the basis of manifestations themselves! Psionics should not be warping reality on any level comparable to Wishes and Miracles! Psionics do not resurrect the dead! Etc. Psychoportation, Clairsentience, and Metapsionics/Metacreativity of the sorts used in 2nd Edition and 3.0E are not much of a stretch, and thus acceptable, believeable as a function of some psionic abilities. 3.5 psionic drek is not.
I'm still on the fence about 'psionic focus' but definitely don't think it appropriate that so many psionic feats and metapsionic abilities now rely exclusively on it. Just stupid.
*shuffles away while grumbling and raving like an angry old codger four times his own age*