Each team should only get two protected rivals, like the pre-Nebraska B1G—e.g., Michigan: MSU, OSU; MSU: Michigan, Penn State; OSU: Michigan, Penn State; Minnesota: Wisconsin, Iowa; Wisconsin: Minnesota, Iowa; etc. No need to protect three games per team with a conference so small.
Also, the conference should go to a 8-game schedule on the condition that teams play their non-conference rival—e.g., Iowa–ISU, OU–OSU, BYU–Utah. I think it's in the Big 12's interest to try to make sure these non-conference rivalries are played.