Oh whoops! Sorry, I didn't see your first reply before.
Vidya would definitely welcome Fi to Hufflepuff with open arms, but the house imbalance hasn't really been an issue at all so I don't think you need to change her unless you really want too.
Approval usually only takes a couple days, but Kendra is dealing with some RL issues and is on a sort of semi-hiatus. Lancis hasn't mentioned any down time, as far as I know, but it looks like he hasn't been online since the 4th :(