I've never been a fan of the subjective picking method at all. I think you should have set criteria, like the NFL does, so there is no gray area. Win your conference for these 6 conferences and you are in. Win 10 games and you are also in, subject to tie breakers if there are too many. Something like that.
In your example only two teams played in that scenario, and you can't effectively "six degrees of Kevin Bacon" them based on conference games later either. It will always be subjective unless there are specific hurdles that you can clear to punch a ticket.