Bishop for drop rate and Lucid support, Kanna for MA% mule, BT if you want to AFK legitimately. Or you can say bishop if you want to second main it or bring it to bossing where your party is expected to need those heals and resurrection to support, Kanna if you've a bunch of MA dedicated friends so you can boost them like some Indian hot spices, or BT if you run into a lot of situations like, "I sort of want to help ma friends but acktually I'm sort of lazy and I've a second laptop coincidentally so maybe I can just log in my BT and you know, leave it there or something", without much thought of it being any more helpful in a boss run (you know, the "real" boss run where you need a party like, Lucid or something else that's ridiculously "strong".
kanna is the best support, HS doesnt stand a chance agaisnt kishin
also 5th job kanna is extreme fun imo
BT is nice to support friends who are making mules and cant clear their maps very fast, after 4th job most will benefit more from a kanna's kishin