I like Fire link the most, where you basically make a connection to an enemy (or possibly an ally?), and anyone between you and the linked character takes damage when one of you move (or start their turn in the fire link, perhaps).
I also like the idea of Enhance Weapon, where you increase the range of your melee weapon, though I think that'll end up being a polymorph spell (from what I remember Swen saying).
Possession could be fun, sort of like a weak charm where you lose your own control to control an enemy, though I'm not sure if the game mechanics would make that easy to implement.
Healing Blossom is also neat, though again, don't know if it needs to be channeled. It'd be kinda cool and bizarre if when it exploded after 3 turns, say, it actually dealt damage instead of healing, so you could use it as a staging area while enemies come at you, and by the time they get there, it'll explode and hurt them instead.
I'm not sure if the Linked Spell concept is necessary, though it would open up new options. I'd probably just call it "Channeled." Basically, the idea is that if you get stunned or knocked down while channeling, it'll stop the spell? I guess there's room for allowing damage to break the channeling too.
