Soraka

W: (600/700/800/900) 1,000 +(90% AP) (15/20 second cooldown 1-3 then 4-5) | AOE (approximately Darius Q size) with a 5s channel and a 20-second cooldown. This way it could probably reward a good Soraka that manages cooldown timers for both her abilities and the enemies CC. ; Normal cost? R: (1,000/2,000) 3,000 +(100% AP) (5 minute cooldown) | 10s channel, requires at least 2 teammates to be below 50% health before activation. Soraka only heals for half. (Maybe even add a little thing like, Soraka has to be near, or even targeted by enemy champions/epic monsters in order to activate as well, so she doesn't abuse this high healing power from base.) (This still might be pretty broken, but I don't know how to make it look like an actual ult. But this is the general idea.)

At the very least, I'm pretty sure it'll drop Soraka's healing rate in two ways. There's a high potential to stop both pretty easy, and her W now does something like twice as much by the time this ideal W is back up.