Flying-based team

Assuming that you intend to use the first three flier units you mentioned there than your answer is Elincia. Even with a neutral iv (i have this one) she is still great. This would also help keep your team balanced and able to respond to most situations. The other option is to shuffle your team a bit more and add both Elincia and F!Morgan since that would give you a ranged flier and with those ivs F!Morgan can be built as a great mage bait unit. Sanaki is the obvious drop in both cases but in the second case i would probably cut Myrrh for F!Morgan if you decide to go that route. Myrrh is a great bait unit but having the chance to include a mage flier probably outweighs her spot and removing the only flying dancer is a nonstarter.