On the subject of spell point costs for ED abilities - and I've been thinking this for a while - they should be reduced.
Across the board.
Seriously, if the point about Epic Destinies is that you might find yourself using any of them, then abilities twistable from any destiny SHOULD NOT require spellpoints to use. Grandmaster of Flowers abilities (at least the twistable ones) should not cost ki. NO abilities should require specific feats. Fine that they should be synergistic / more beneficial with classes having particular feats (or a ki bar, or a blue bar, or whatever) but they absolutely should not require those things. Cooldown is enough of a limiting factor. If I want to summon forth a mighty wave of water (and go to the effort of slotting the spellpower to make anyone care) on a pure Fighter, or Energy Burst on a Barb, I should be able to. If I want to twist a melee ability on my quirky battle-Sorc, I should be able to without needing a feat that's of little use to me otherwise. If I want to twist in a minor ranged AoE (Orchid Blossom) on my AA for a little extra pew-pew it should work. Never mind if it's gimp, that's not the point.
Similarly (and yes, I'm saying it again) ALL Epic Destinies should offer EVERY stat as a potential increase, ALL ED abilities doing something for casters of any type should key from the highest of Int/Wis/Cha, and every ED which offers caster levels should grant them for any casting class. Heck, for every class. It's not like they'd be giving you spells on, say, a pure Rogue; you'd just count as having a few notional caster levels in any class you needed them for (if you were in that Destiny), and so what?
Limited flexibility is limited.