Okay then, Ren is pretty good, however, there is one issue myself and Krinos have with her spells.

Froststrike and Galestrike did NOT exist within the VI realm, therefore, they are not available to your character, other than that, you're perfectly fine to join the battle, remove those two spells, change them for Blizard and Aero if you so wish, but you cannot have them as they are.