The RPI was straight forward. Your record, your opponents' record, and your opponents' opponents' record, with an adjustment for home and away. Everyone understood how it worked, and no one could complain when they finished the season with a low RPI. The only real complaint, that some high majors gamed the system by playing a lot of mid-majors is way overblown. Playing decent mid major teams is a risk, because those teams occasionally beat the high majors. If a team is willing to take the risk and play a MAC or MAAC team instead of Central, they deserve the reward.
NET rewards running up the score on bad teams. Leagues like the Big 12 have already cut back on major conference opponents, because why bother?