Agree Cat brackets wouldn't work for every fighter in a div. Some idea's that might lead to a better system. Bracketing top ten with a points system were other still gain points to possibly jump from say 16 to 9. Points could come from a win, record, strikes, takedowns, Ko's, Sub's, control, showmens ship, and ect... Lose points by turning down fights chosing to take time off/ basically be able to fight 3 times a year/ be avalible to fight after 100 days or lose points. Hopefully this would give a strong record of top 4 to show who the next contender should be instead of crazy match making we have seen lately for titles.
I know this isn't perfect, but a starting point to something better hopefully.