i always thought that each individual conference should have the same base prestige for each of its teams.
Take the Top-6 conferences, and every team in each of those (72 teams) would all be A.
This would be for the:
ACC,
Big 12,
Big East,
Big Ten,
Pac-12 and
SEC.
The next 6 conferences would be at B...
A-10,
Mountain West,
West Coast,
Horizon,
Missouri Valley
C-USA.
The next 4 conferences would be at C...
MAC,
Colonial.
Ohio Valley.
Big West.
The remaining 11 conferences would be at D.
So groups of 6-6-4-11. And base prestige for all at A B C D.