Serra's usefulness is really rather limited. She doesn't have a lot of time as the team's only healer before Prissy shows up and basically outclasses her. Plus base Magic of 2, and the only time I used her she had a whopping 6 Magic upon promotion. Of course, she does heal and has a few maps of free deployment, and can come up with a clutch heal or two before we get Priscilla.
5/10