Looks like you have a good 5* for everything except a tank. If you're looking to round out that way, Effie would be your choice.
Though in terms of team building I would go with
-- Lyn, Reinhardt, Olivia, and Kagero
Lyn + Olivia actually has a chance of procing Galeforce for 3 attacks in 1 round, while Kagero is the best ranged unit after Takumi, and Reinhardt can protect the entire team with his 5 tile range.
-- Lucina, Effie, Kagero, Nowi/Corrin(f)
Lucina is just incredible. Effie and Nowi/Corrin(f) will take care of your front line for you while Kagero goes on a rampage.