well grace , fignelia and camilla are the obvious choices. Actually , i'd raise and aw camilla first because shes quite a bit better then her sister (i have one on my main)

Grace is a black , and by that fact alone , she's very strong. On top of that she has a rather powerfull skill and a great AW passive.

As for figelia...well she's a great DPS witch , but that's pretty much it. She's going to hit llike a truck , but i don't see her as a high priority. At least not over the other 2 anyway