I'm kind of glad that Regen and overhealing gives regular enmity. It was stupidly overpowered in 1.0 and now i actually have to make a conscious decision of what to use and take hate into account. Otherwise fights would easily be Medica II spam nonstop.
Instead of tossing Regen on someone that took a stray hit just use Cure, even better you have a chance of triggering Freecure. Throw out a Medica if 3 people or more took a hit. It just takes practice and getting used to the new mechanics and I have to say I've acclimated pretty well.