I love the idea but you can't play the all 3 rounds of the playoffs at neutral sites. The games wouldn't have the attendance necessary. The average college football fan can't afford to take off work and fly to 2 or 3 different places in a 3 week span. So then you'd have to pick...should I go to the first game or take the risk that we don't win the first game and buy tickets and airfare to the second game?
Yes you'd have some neutral fans from around the area want to go...but I don't see it working long term.
The higher seeded teams need to play the first game at home and then have the final four at a neutral site.