I would love to see all conf champs get in, but some type of qualifier to weed out the any team/conference who is weak. the example of a situation like N Texas winning their conf with a 7-5 record should exclude them. Have no idea how to do this as I don't want it to become a beauty pageant. And the qualifier should be fairly liberal...maybe you need to be in the Top 30.
The other thing I would love to see is an overhaul in the system for determining the at-large berths and the seedings. Put a LOT more weight on SOS for OOC games and for those being road games. So Alabama could go undefeated in the SEC, but only get a 7 seed because their OOC schedule consisted of Eastern North Carolina, Sam Houston State and Idaho State...all at home.
This would accomplish a few things. Drive more good/interesting matchups. Force teams to travel. And it would help to gauge the relative strength of conferences. I think a safe bet that if the SEC traveled to the west coast and/or to the north (especially late in the season) and against opponents with a pulse, their OOC records would take a significant dive.