The "magic" numbers for expansion are 16, 18, 20 and 24
Odd numbers are definitely out. After 12 members- as we see now even numbers are not enough. Numbers divisible by 4 or 6 to make scheduling far easier. 18 is not a "clean" an number as 16 or 20 as it's not divisible by 4.
24 is the "super number"
Four groups of 6
Six groups of 4
Three groups of 8
Two groups of 12
None of these groups would have odd numbers
20 works well because of the odd number at 4/5 level as five teams in a pod/subdivision means and even 4 games within the group (2 home/2 away) Leaving plenty of games within conference.
I abhor the idea of 9 conference games. HATE it. Would prefer to see them league skip to 10 games to assure the same number of home/away games for all teams- especially if the SEC forces the neutral site games to go away. (UF/GA; TX/OK; etc)
12 games. 10 conference games. 2 against FBS opponents only (preferably 1 road/1 away or neutral)
I like the concept of four- 20 team conferences. 80 teams
Those 80 teams have complete autonomy over their rules including scholarship limits, officiating pool, membership requirements, and championships. Schools wishing to join the EIGHTY position the conferences and not the NCAA.
And why not institute a "relegation" provisions. Schools not meeting requirements (wins, attendance, grad rates, money spent on athletics, etc) are relegated out of the Eighty and replaced by next school in line. Would weed out the "hammock class" in each conference that soaks in the conference money while doing little for the student athletes or growing their sport.
The EIGHTY would be be the EIGHTY in all sports. Meaning separate championships for all sports.
We'll call it the "Collegiate Premiere League". It may take leaving the NCAA to get this done but would also prevent the NCAA from being sued by the lesser members trying to open the door for themselves.