User blog comment:Collbrande-Ex-Caliburn/Hyoudou Issei's Peerage composition hopes/dreams/hypothesis/@comment-10330822-20161112235347/@comment-9595671-20161120164030

I didn't realize Azazel mentioned that, so your saying that if they can create a successful way to trade Brave Saints with Evil Pieces then Irina could join him. While she is Michael's ace, Vol 22 did show it is still possible to contact everyone trapped in the Trihexa seal, so I think he could still do the trade.

I do agree that Issei's team will likely be very diverse, Rias team was very much like that since before this volume she had a dragon, a nun turned devil healer, a holy devil sword user, the wielder of durandal, a human/fallen hybrid, a dhampir, a nekomata and a valkyrie.

Diversity is important in rating games too, if your peerage's powers were too similar that could risk an opponent easily wiping you out if they found your servants' weakness. That's a trait I've only seen in Diodora's peerage since it was fully comprised of former church members.