As much as I like the idea of having Jinchuuriki, there is no practical way to do this anytime soon.
Spending the amount of development time required to create Jutsus specially for each Jinchuuriki and managing them for the sake of 1 player, is too much work. We could better use the time create more fun content for everyone to enjoy.
Not ruling it out, but for the time being, I'm making Bijuu - high level bosses with rare drops
Edit: Isobu I really like the 4th Mizukage sprite in your signature! Good job.