I'd prefer that Ms. Liberty take up the FP Tanker Status, have the new Fan created character join the Vindicators.
-It would make more sense story wise to handle it this way, and it could be used as a good story arc where finally we get a Sidekick character that takes over for their mentor. Story wise have some incarnate energy infect the Liberty Belt, which alters Ms. Liberty's powers to a more tanker type set. Have the fan created character be part of the arc as well. The end result would be Ms. Liberty joining the FP, and being the Incarnate signature character, with the Fan made character joining the Vindicators.