Similar to how the CFP has all but ruined bowl games, going completely at-large would devalue conference games/rivalries/championships. In the NFL, a week 17 matchup between the Packers and Vikings is way more compelling if the winner gets a playoff bid by winning the division. I beleive that they have the closest to perfect model of what playoff seeding should look like. College football obviously can't put the same percentage of teams in (37% in the NFL's case), but hte division/conference winners + at-large mix seems right.

I think there needs to be a mix in CFB. Give the P5 their 5 spots for conference champions. For the last 3, either do 3 at-large or 2 at-large and a G5 representative. 

I'm on the fence about the auto-bid for G5 for the following reasons (Full disclosure, I'm a fan of an AAC team):

Against: At my core, I beleive that if the G5 can't produce a top 8 team in a given year, they have no business being in the playoff. Plus, if the AAC were to produce the 6th-7th best team, for example, it would stink if they were still automatically slotted at #8 against the #1 because "it's the G5 spot".

For: I'm not naive about the bias of the committee. While I see the AAC getting more and more teams into the rankings each year, I'm realistic about the idea that a glass ceiling exists. That had Houston gone undefeated in 2015 after beating Oklahoma and Louisville, they'd be stuck at #5 in the current format, or #9 in an 8-team format. For that reason, an auto-bid might be the only chance we'll get to prove that we belong in the playoff. If we get bounced in the first game, that's fine, but we'd like the chance to settle it on the field.