First, I have to say that I can't imagine this story ending without a Guriko-Hana rematch.
Second, I think it's important that Hana does end up taking the top. Like Zetton said, Suzuran is missing something. It needs to be more than just a place where really strong guys go to fight each other and try to come out on top. Hana gives the school a "heart" of sorts that it's been missing. It would screw up the moral of the story if he wasn't recognized as the leader.
That said, I could see it ending with a bunch of splinter groups, like LO said, and Hana et al coming to accept that there will always be guys who don't buy in. It could be alright, if it's done right.