Odin wasn't too bad for me personally. I beat him on the first try, but had some close calls throughout. Here's what I did:
Entered fight as Com/Med, no fortisol or aegisol. (Though these would surely help) Switched over to Rav/Rav and hammered him, switching to Rav/Med as necessary to heal and popping potions when I was cutting it a little too close. If Hope had Synergist at this point (I don't remember if he started with it or gained it by this point or whatever) I probably buffed before going on the offensive. Just make sure you Rav/Rav when you don't need healed and when he's doing the shield move, and Rav/Med when you do need healed, and you should be fine. Also, I never once used Med/Med during this fight.
Honestly, he really isn't that bad. You just need to be fast with your paradigm shifts and you should be fine. I did not have battle speed set on slow, by the way.
Currently playing: Final Fantasy XIII (LOVE IT) Anticipating: God of War III, Resonance of Fate