I may be biased, but Bernice is a great choice seeing several maps need a really strong and active tank, and she's one of the best we have so far. She has saved my ass a few times now with her extra block, and even if she's 2 UP more expensive, she makes up for it with her good defense, and when S.AW comes she will certainly benefit a lot of it.

Belinda is also a great choice to buff up your witches as Kyanon said, and since she's min cost you're going to benefit a lot from putting her first. Fedora could be another choice too because of the -1 to her cost, Imelia also could be a great choice however do note that her skill only works on bandits for the health bonus so that's mainly when you run 2-3 bandits as your duelists of choice. Noel, well she is a special case if you need another mage and it goes with the plus of extra G per run she is on the team. Bashira also turns into a great choice but if you do it, her ability could backfire in maps where ranged and flying enemies come at the same time and she will go for the ranged ones. This particularly can mess up some strategies.

Judging by your main team, Imelia and Belinda turn into the most useful to AW in order to buff your team (In Imelia's particular case you'd have to take swap someone with her). Noel is a different case just for the extra Gold per run she is in team.