Looks like a system that doesn't believe 3 of the top 8 teams in the country could possibly reside in the same conference.
Cute.
We have had this debate before so I'll keep this short:
First:
Bwar's example, and what I think the eventual 8-team playoff will be, will have the P5 Champs, the highest ranked G5 Champ, and TWO at-large teams. Thus, one conference could get three berths (Champ and two at-large).
Second:
In theory I agree with your position that the playoff should at least strive to get the best two, four, six, eight, or sixteen teams regardless of conference. In practice, I think this is extraordinarily difficult because there is so little inter-league play.
I think most of us *think* that Alabama is the best team but their toughest OOC opponent is a Louisville team that went 8-5 last year.
Most of us *think* that Clemson is a really good team but their best OOC opponent is a USCe team that went 5-3 in the SEC-E last year.
Most of us *think* that Georgia is a really good team but their best OOC opponent is a GaTech team that went .500 in the ACC last year.
Most of us *think* that Wisconsin is a really good team but their best OOC opponent is a BYU team that went 4-9 last year.
There isn't very much high-end inter-league play which means that we are always left to guess how good the best teams in the various conferences are relative to each other.
Finally:
A system like what Bwar listed would allow up to three teams from one conference. I frankly think that is more than enough. A lot of people here make the case that you can't be the best in the Nation if you aren't first the best in your conference. That line of argument would have excluded Bama in 2017 and Ohio State in 2016. I take a middle road between that position and yours. I think that with tiebreakers being what they are and the absolute advantage of playing at home, sometimes the best team doesn't win their division. Bama in 2017 and Ohio State in 2016 both lost a road game then tied for their Division Championship and missed their respective CG's because of their road loss. I think that HFA is real and that both Bama 2017 and tOSU 2016 were the best teams in their conference. However, if you aren't in the top-3 then I don't think you have much to complain about if you are left out of the playoffs. I have trouble imagining a situation in which a fourth team from one conference would have a sympathetic case for inclusion.