Tournaments are the purest way to crown a champ no doubt.
You watched that Jones press conference too eh....
Ideally the divisions would be built up where the booking was essentially shadow tournaments, at least for the top of any given division. Not everyone would have to beat the same number of challengers, but once someone got high up there you could have a plan for the next three title shots in a row. Joe Silva did something similar to this, and we're seeing the cost of his absence. If MMA wasn't such a depressing affair these days I'd write up a more in depth example, but the basic gyst is:
Example Featherweight Title Feed:
-Next shot: Yair Rodriguez vs. Volkanovski
-Shot after Next: winner of Chan Sung Jung vs. Zabit Magomedsharipov
-Shot after That: winner of Holloway/Stephens vs. Burgos/Emmett
-Some matches to help line up Shot after THAT: Bektic vs. Kattar, Ryan Hall vs. Lamas, Ortega vs. Moicano, loser of Rodriguez/Volkanovski vs. Edgar
Unfortunately current hotshot booking has made it so most of these people are currently coming off a loss, and you'd need some reserve bouts in the mix (like two or three more), but this is just an example of how it could be done. No actual published brackets, and people can be switched in an out (fight like Jon Fitch you get slow-tracked, fight like TKZ you get fast-tracked), but having a continuous supply of credible contenders planned out 20 months or more in advance is totally feasible in the deeper divisions, but the UFC just doesn't care about the credibility side of things.