seriously, isshin fits any pve team. you'll gain no bigger benefit after adding him to your rotation. if you want a support, kenpachi unohana is very nice.
Get isshin first and then sogyo and then you have my team it fits really well together with ori/Sexy yoru giving the sword dmg buffs and then soygo giving the circle buffs. with that formation a bankai sogyo gave me the same dmg per hit on my ES as my hogyokai zabi. and use 9th skill until you get sogyo, once you get that switch to 5th