The combination of Ars Énergistique and Applied Flux should make it possible to power everything with source either directly or through conversion (whether or not it’s practical remains to be seen). I’m currently on a version from before create was updated and won’t be updating the pack unless Ars Creo is compatible as well.
In case anyone comes across this in the future, it turns out that Applied Flux will NOT convert AE to FE as I originally thought. It essentially turns power into another “item” that your ME network can handle. It’s nice as an alternative to using Flux Networks everywhere again, but it can’t accomplish my original goal.
I haven’t tried those mods but hopefully they buff the conversion rates. Historically, magic to RF has been a terrible deal in my experience.
In my own world I got around this by using cross-mod shenanigans to dupe diamonds, then burned the diamonds for fuel. That seemed sufficiently magical for my headcanon