Thanks for the interesting thoughts! To avoid over-complicating things, I think we will want to avoid delving too heavily into non-pagan faiths. The reason I am open to the inclusion of religions such as Egyptian paganism is because they are entirely compatible with Hellenism -- there is a belief of infinite gods. Many Romans worshiped Egyptian gods, and many Egyptians worshiped Greek gods. Abrahamic religions are entirely incompatible with this mindset -- hence why they never managed to coexist in history. I was (and still am a bit) even hesitant on Persian figures because much of the Western understanding of Persian paganism is filtered through how the Romans understood it, which could very well be just wrong.
However, the conflict between Abrahamic religions and pagan ones is very interesting, and I would certainly be fascinated to see a character who's modern religion is incompatible with the religion of their past life. I would certainly encourage exploration of that. As a whole, though, no, we probably won't be utilizing non-pagan religions extensively.
Also, I have class and work today, but tonight I should have both an ooc/signup thread and a Discord posted here, so please keep an eye out for that! I'm so hyped about all of the discussion so far, so I can't wait to get started :)