My favourite heals are the glare machines, that say "I have co-heal for that" and try to out-DPS others. Happened while farming Emerald Weapon back in ShB along with PLD with golden parses that ate half the AoE's.

Idk If you pick a healer then heal, even if it's a sprout that works as a floor tank or BLM that eats all the aoes. We're not in savage where heal DPS matters so much you can't overheal much.