On the whole, you've already heard my spiel: have healing GCDs grant gauge that can be used to rush cooldowns, with a couple new non-curative cooldowns being added to WHM. No Misery, just indirect potency recovery, perhaps with returns that increasingly diminish over use and then recover over time. Let summoning a Tornado to wreck and CC enemies while hastening nearby allies' movement speeds or a Quake to again damage and CC while providing cover to allies, at greater frequency as healing intensity increases, be sufficient.