Should I keep renewal or go with mystic boost on her?

This is a case where renewal might be just as good as Mystic boost, since you're using her as a semi-healer. Because in order to heal Camilla, she has to attack, which means she can't heal anyone else that turn. So if she heals an ally with Reciprocal Aid, she has to then attack for a turn or two before in order to heal herself up to be able to heal again. (and hope that her combats don't result in her taking more damage.) with renewal, she can passively heal herself without being in combat, giving you more options. Plus, considering how premium of a skill MB is, I'd stick with Renewal

If you're often going to give your HP away, I'd say renewal. You want to be able to stall for more HP.

Also, I think it would be good to avoid fury if you can. Over multiple engagements the recoil will start to add up unless you're getting doubled a lot.