You aint specify which version of Kabuto. Im taking 4GSW Kabuto as my mentor and learning everything.

It’s Kabuto in general. You can pick whatever version of him.

Kabuto

Oh then absolutely Kabuto, why would we NOT pick him? Even in Part 1 he was on par with Kakashi, and he only became stronger from there.

Considering his smarts, he could probably just give his student like every conceivable power via surgery.

I don't know because I think you can learn something from everyone except Ino and Kidomaru. Hinata is my favorite character, but I couldn't imagine her as a coach. So I choose Kabuto I think.