I'm willing to help with feedback, fluff analysis/writing, etc... But my knowledge of the planes is more heavily focused on Baator. I can provide feedback logically, but not from the past.

I am a wellspring of ideas when I'm not being odd.

Before we focus on any of the players/characters, we need to look at positions and organization. I also highly recommend making some distinctions between the different Good outsiders: we have Archons, Guardinals, and Eladrin, plus Angels. That feels very over-Killy to me, but I'm odd and I realize evil has 4. But a distinctive note on the different structure is good.