yes i'm suggesting things like 16 persons tournaments, or 8 persons seasons with division. Cancelation and changes are not a big deal because you have it in any format (khabib/ferg, zabit/yair...mcgregor/diaz...). You can have a rule of replacement, or even forfaits.
Another format i would agree with would be something with a clear point system for rankings. Based on who you beat (ranking wise) and how if you want to avoid too much wall n stall. For exemple : victory = 10- opponent rank (depending on the depth of the division) + 5 for Rd 1 finish + 3 for rd 2-3 finish + 1 for dec. And if you want to add some more spectaculus control : +x for fotn/kootn/subotn etc, even PPV numbers or instagram followers may add points, ahah !. You put rankings at 0 (or more, maybe) every 2 or 3 years. You can go on match making, but you would have a clear ranking, and you could rule something like title shots are obligatory for the man with the better ranking + you can't have 2 title shots in a raw (no instant rematch, maybe except for specific circumstances : a champ may have granted an instant rematch if he loses after 3 successful defenses).
Do you like this UFC of mine ?