Fire: Amaterasu, Svarog, Uriel, Ares will work for now. You'll want to replace Uriel or Ares with Mars, maybe with the next Miracle ticket.
Water: Cthulhu, Snow Raphael, Aphrodite, Ryu-Oh. You can run a Burst build that should be pretty effective, particularly if you use Vicissitudes of Fortune as EX. Athirat and SSR Nike could slightly improve this build by sacrificing overdrive extension for a Burst gauge buff.
Magicami Starter Guide: Rerolling for Success
Rerolling in Kamihime Project: How to get FREE SSR Kamihime
Sanahtlig's Kamihime Project Toolbox: Includes damage calculators and other useful tools, data, and info I've designed and collected. Make a copy to edit.