I put together a playoff using the Bowls back when the BCS crap started..and you surely could use the Bowls. One of the reasons some say they don't want a playoff, is because of the History and tradition of Bowl games. (Plus the money..don't forget the money..although, they don't say that)
I believe there are 120 NCAA Division ! schools..and 34 bowl games..meaning 68 teams play in a Bowl of some magnitude.. that is over half of all Division I schools.
Take the BCS and the Top 16 Teams...and seed them 1-16...you'll need 15 Bowl games for the Championship..leaving 19 Bowl Games for the rest of the teams..(or 14 Bowl Games..as currently..the BCS Championship Game is not played in a Bowl..so..using the Bowls as I describe would leave 56 teams playing in Bowls..or almost half the Division I schools)
Under the current setup..34 Bowl Games=68 teams Under my idea 34 Bowl Games = 54 Teams.. Or 34 Bowl Games=56 Teams..if you have a NCG outside of a Bowl. That's still almost half of all schools going to a Bowl game.
So you lose a bunch of 7-5 and 6-6 teams..
They'd have to juggle the schedule a bit for the bowls..but they should be able to do this..all bowl games used to be finished by Jan 1st..now..there are 9 bowl games which will be played after Jan 1st..
Using the BCS to determine the Top 16..would leave your playoff teams as :(Ranked using the BCS)
Start with the Insight Bowl #1 Alabama Vs #16 West Virginia(I think that would outdraw 6-6 Minnesota Vs 6-6 Iowa St)
Outback Bowl Features #2 Texas Vs #15 Miami(Fla)
Capital One Bowl would have #3 Cincinnati Vs #14 BYU
Gator Bowl #4 TCU Vs #13 Penn St
Chick-Fil Bowl #5 Florida Vs #12 LSU
Sun Bowl #6 Boise St Vs #11 Virginia Tech
Holiday Bowl #7 Oregon Vs #10 Iowa
Liberty Bowl #8 Ohio St Vs #9 Georgia Tech
Those Bowls would probably generate far more interest and $ than some of the current matchups..
Just for the sake of this post..we'll assume all Top seeds advance..
Champs Sports Bowl hosts #4 TCU Vs #5 Florida
Alamo Bowl #3Cincinnati Vs #6 Boise St
Cotton Bowl #2 Texas Vs #7 Oregon
Sugar Bowl #1 Alabama Vs #8 Ohio St
Then Fiesta Bowl #1 Alabama Vs #4 TCU
Orange Bowl #2Texas Vs #3 Cincinnati
Rose Bowl = National Championship
(Or as I said..eliminate one Bowl game..as the BCS currently is not played as a Bowl game..and leave it for teams that didn't make the Top 16..ie..playoffs) That would mean..once the Bowls ended..you'd be left with a National Championship Game.. They could figure out how to split up the money..(or maybe not..as this appears to be the BIG reason..there isn't a NCG and playoffs)
I'm fairly certain these bowl games would generate far more revenue as part of a playoff system..than they do now.. This would mean..that some other Bigger schools..who don't make the playoffs..would trickle down to the "lesser" bowls..and thus..those "lesser" bowls would make more money too.