I'd keep Steelskull since he's good for Faction Wars and all around early progression. Tagoar has a full team revive which is solid early and great for Faction Wars too. I'd keep Jizoh for now just so you have Provoke. And Aothar is a middle of the road poisoner, good in CB and worth keeping.

I wouldn't bother keeping any of the other champs myself, keeping in mind you will need at least one copy of some of them to do the fusions (they have the white swirly icon on them when you go into the tavern, and you can check them all out in the fusion section of the portal.)

Campaign farmable champs like Templar, Executionor, etc.... you will get tons and tons and tons of them over the time you are playing and can always go get another. So they are relatively safe to use for that early game rank up food grind. Side note: Warpriest they give you early, but she's food through and through.

Other than that, the "best practices" is to stick to leveling up uncommons and using them predominantly for food.

Thank you SOO much! This gives me great direction and so appreciative!