1 side is the rules side (aka the committees/subcommittees made up of reps from the various schools) and the other side would be the admin and monitoring side (aka the side that receives its paycheck from the NCAA). The Admin and Monitoring side would be responsible for the hiring of the Commissioner. The Admin and Monitoring could even hire a headhunter or establish an independent committee of consultants to handle the hiring process. Even though the Commissioner may rotate the NCAA could be structured to also have an executive officer that would be responsible for having the final say on who is hired as the next commissioner.

Given that everyone in the Commissioner position will have a college degree (maybe even multiple degrees), the only way you can avoid having a Commissioner with a degree from a DI college/university is to only people with a degree from a DII, DIII, or NAIA school which I think could be a form of discrimination. The search process will have to vet candidates to ensure that the Commissioner is putting the interest of the entire NCAA above the interest of individual schools. It also, means the enforcement of the rules are consistent across the board regardless whether you are UNC-Chapel Hill or UNC-Wilmington. At the very least it could do a better job of selling to the public that within the organization there is a clear separation of church and state.