Biggest fix would be increasing revenue share from 15-18% to 40-50% for the fighters...that alone would make the floor on pay so much higher that becoming a UFC fighter would be a serious accomplishment. I'd also say do away with win bonus pay unless a fighter/agent wants that in their contract, it's a bogus standard though. If the pay floor for fighting in the UFC was 50-80k (I know 80 is kinda high) it'd really make things a lot better.
Besides this? I'd love to see the UFC do a combine of sorts for prospects to sign each season, where they go over their records, the gyms they train at, their age, killsets, accompligsments etc. Along with some athlstic tests and whatnot. Regardless I'd like to see the UFC become more meritocratic and focusing on skill, talent and potential rather than marketability, style and nationalistic quotas.
I also wish they'd be willing to pay for top talent when/if they reach free agency. It's wild how they pass up on a 25 year old double champ in Salahdine Parnasse but threw money at a 35 year old Michael Chandler...fucking hell. Guys like Keita, Vartanyan, Christian Lee etc shouldn't be in other promotions because they will get paid a lot more than the UFC would pay them...if the UFC is supposed to be the NFL.
I'd also like to see fighters more active if they're able and wanting. Maybe that means a slightly smaller roster number or slightly more cards but fighters averaging 2 fights a year is absurd and makes the sport feel so slow and worthless to follow sometimes.