I have my MMMMP group set up so that if I'm attacking something with my single-target DPS mapped key, the mages cast their things and the priest does not heal, she just becomes a manual healer via Clique+Grid2. If I'm using the AoE DPS mapped key, the priest will maintain bubble, renew, and spam heals on @targettarget; if the priest doesn't have a target and I'm spamming AoE, it does nothing and reverts to manual click healing as above. Works pretty well as a semi-automatic, least-effort-per-reward setup for me. I also follow Peregrine's leveling guide as nodoze mentioned.
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