Well, since there's a lot of swords on the team.. why not try killer B? Wind blade would be devastating if you could pull it off. I'd never say its a bad idea to put in GNW 1010 though. You would have to hide her behind a little bit of beef if you do.
Honestly, for this team to work, you need to go true to the lightning main's usual and go for a sword team. It's to squishy to do anything else. a Mabui might give a shield to help along with some heals (knockdown-knockdown is easy to fit in with mifune :P) but you need to do as much damage as possible as early as possible so i wouldn't suggest her. Naruto definitley works though. tanky enough to take a hit and does good damage.
Have fun with your draw and play around in the arena to playtest :)
GZ on Cho!