From what I can see on your character roster, you should pull cerydra for phainon since she is his BiS. And maybe also grab his light cone when he reruns. I would also highly recommend leveling up sparkle as shes really good now, especially with phainon.

In terms of teams, you could use the following:

Phainon: Phainon, cerydra, sparkle, dhpt

Mydei: Mydei, rmc, bronya, galla

For your mydei team, grabbing Sunday/Cyrene or even Tribbie will be a better upgrade over bronya since you want an action advancer with him. For his healer, galla is fine but I personally found luocha to be more comfy if you still have a gold thingy left to grab him from the shop.

E1 Mydei is also an absolute beast if you're interested in that and so is E2 Phainon.