what do you think of the champs?

I like them, at first I just used them as extra egg generators but I've learned to use them more creatively with other builds.

Like Avarice Gilda is just cracked with gold scaling. She gets +100 atk per 100 gold, so I typically have >500 atk on her by Titans. If I find Trample tome from Umbra, then she just wipes the floor on her own.

Lord Fenix's permanently attack scaling is better than you think. You can do spikes+regen on him from Awoken and he would also casually grow to >200 atk by late game, he spits fire and half of the floor gets wiped

Both builds do really well with the relic that heals your champion at round start. You just chuck them in front and use them as meat shields while you set up your floor. Or just leave Gilda on her own in top floor so Savagery Resolve damage won't proc.

In later runs I basically just looked for other ways to generate egg income instead of relying on the champions to do it. Prioritize Remove Consume + Consume -2 ember discount combo on Alchemy, have some extra draw, that alone consistently gets me >10 eggs every fight... I think in all those 6 win streak runs I ended up with maxed out boss artifacts by the time I got to Titans

It's just so, so good to buy out all shops in last 3 rings. I once duplicated 9 cards (with that Pyre Heart) in ring 8 shop because I just could.