I usually give it to healer that can balance their dps and healing good and don't just spam Holy like a lunatic ( as much as I love the light of holy but if it just 1 - 2 mob just Stone it )

also if healer just healing all the way then I will give my comm to dps that effect party the most.

for dps I'm not going to give my comm depend on how hard to play that class are but how effective they are in party.