As it's been said a hundred times already, there's no stat based metric to track healing.

I play a Scholar and I'm currently leveling a WHM just to try it out. The biggest obstacle so far is finding people who know how to dodge skills with 4-day cast times. I know it can sometimes be difficult but even as a BLM, it's not hard to dodge. After a certain point, you just realize that certain people aren't making up the MP cost to heal. DPS who barely dodge, if ever, and eat up half of your heals aren't cost efficient. I'm the healer who purposely lets people die when they don't show the ability to cover their own asses. Unavoidable AoEs are one thing, being completely blind and eating 10 Titan EX AoEs are another. Some people are better left face down.

However, this is why a lot of people run with statics instead of pugs. Personally, I prefer pugs for the entertainment factor.