Aquiline Cross
Prereq could include "Know Remove Affliction and Resurrection rituals."
Not all divine classes grant healing. Action point thing could just be, "When you spend an action point, you may have an ally within 10 squares heal 2d6 hit points." (Is that too little at paragon level?)
Lifted by Faith. Solid. Strong.
Clinging to Life. I'd adjust the wording. "Allies within 5 squares of you gain a +2 bonus to death saving throws." (The wake up on 18-20 is inherent in that, and could actually get confusing if they have a bonus to death saves from some other source.)
I do generally suggest some manner of offense in the powers, even if it's indirect, just because, well, combat in 4e takes so f*****g long. Like maybe level 11 is "All allies in burst can make a saving throw with a +2 bonus. They gain a +2 power bonus to attack rolls until the end of your next turn."
Dispel Curse is groovy.
Resurrection . . . that's getting into epic destiny "resurrection power" territory. Not to mention it saves the party a lot of money. Maybe something like Close Burst 20, one ally within burst, immediate interrupt when an ally would be reduced below 0 hit points or die. The ally is healed as if he had spent a healing surge, and can stand as a free action. If the ally would have died from failing a death saving throw, he's treated as not having failed the save. The ally's initiative moves to right after yours and gains +4 to all defenses until the end of your next turn.
I dunno. I'm not sure what works best. Maybe you should, like, summon a giant eagle spirit or something.
Lyceum Adept
I'd up the prereq just a tad, to "Any arcane class
and any other non-martial class."
Scholastic Knowledge and Arcane Insight are great. Maybe make it "any implement encounter power of level 11; you can retrain this power later as you gain levels. Treat the power as one from your class, so you can use your implement with it." (Probably not broken if you allow wizards to learn fighter powers, though. This also lets sorcerers apply their damage bonus to cross-class powers.)
Ritual Mastery or something like it shows up as an epic destiny power, I think in Arcane Power or FR player's guide. Maybe weaken it slightly to, "Once per day you can expend a daily attack or utility power to cast a ritual as a standard action. You must expend the normal component cost for the ritual."
You really don't like attack powers, do you?
Arcane insight is kinda boring, just granting a save. One thing I've always wanted to see is an encounter power that says, "You use an at-will implement attack power that one of your allies within 20 squares knows. The attack and damage rolls are modified by Intelligence or Charisma, and you can use any implement you're proficient with."
Sticky Effect could end up redundant with orb wizards, and it doesn't fit the theme of 'learning magic of many varied sources' as well as it could. Maybe something like minor action, choose a damage keyword. The next time you use a power you can have it deal damage of the chosen keyword instead of its normal type.
Or maybe at 12th level, the PC just gains a free multiclass feat, even if he or she has already multiclassed.
How does Learn Power interact with monsters that don't use class-derived powers? It's a cool idea, but it's either really niche (how many enemies are built with class powers?) or really versatile (why yes, I will mimic the berbalang's "duplicate self" power).
If you want to go for balanced versatility, maybe make it, Daily 20, use any daily attack power you know of level 20 or below.