You need everyone working together, acknowledging that everyone is better off if they are incentivized to succeed by investing in themselves first. Then the rewards will come. Here are the issues with just creating a "best of" conference:

1-The TV & CFP revenue wouldn't be nearly the same. If the core schools are down there's no one to pick up the slack.
2-You've got no guaranteed auto bid. You'll end up with another Boise State, Hawaii, Western Michigan, NIU, etc. stealing bids from outside the best G5 league.
3-G5 programs are very volatile, meaning the bottom is really bad (UCF was 0-12, USF was 2-9, Fresno was 1-11, and Cincy just had back to back 4-8 seasons)

My proposal would protect against a lot of these issues and make sure the best teams were being rewarded for on field success.