That Israfael at least. If I had to stat him, I'd peg him at about CR 130. Most likely if he shows up he'll be a Power in a similar vein to Eblis (That is that despite being technically lower ranked he's more powerful than most of the Hebdomad).

As for Barachiel's ability I would suggest keeping it mechanically the same but add meteors, pillars of fire, raining acid, locusts, stuff like that. Don't worry about it if Israfael is going to show up.