This OVA will get a sequel with the last of the Shippuden DVDs.
Too many things are Left Hanging
Itachi is an undercover cop.
Because it would match up with his canon role
The Hyuuga are a Yakuza family and Tsunade owes them money.
Because this would explain them being okay with Hinata's relationship with Naruto and why Tsunade's letting the whole situation play out rather than taking disciplinary action against the violence in her school.
Following the logic of the above guesses, Hiashi will be the principal in the sequel.
As noted above, a sequel is needed to tie up the many loose ends. Tsunade has mortgaged the school's administrative rights as surety for her gambling debts. Unable to repay her debts, she loses the administrative rights to the leader of the local Yakuza syndicate, Hiashi Hyuuga, who promptly appoints himself as principal because the money's good and it strengthens his ties to the community, making it harder for any legal crackdown to operate.