By usable I meant can I use who I want to use and still accomplish things as Thunder even if it's not optimal. I'd rather not spend any cash since I know I'd spend much more than what I'd intend to spend lol.

I have 2 (3) rerolls saved. One has Brahma & Kingu while the other has Athena & Set (or w/e her name is), which would be a better start? I have another reroll with only the 100% Thunder eidolon I could add as a friend, or should I continue rerolling?

Thanks for the help.