Here are the best winning percentages for current non-P5 teams for the 20 years from 2000-2019 (I'll stop at 16 assuming we don't need more than that for a "conference"). The rank is overall national ranking so all teams not listed are P5 already. Also, I only included teams that were in D1 for at least 18 of the 20 years:
- #1 Boise, .83588
- #24 Toledo, .63200
- #26 No. IL, .62109
- #27 BYU, .61961
- #29 Cincy, .61811
- #38 UCF, .57769
- #39 Marshall, .57540
- #41 Fresno, .57308
- #44 Navy, .56917
- #46 Air Force, .56400
- #47 USF, .56034
- #48 Houston, .55556
- #51 Troy, .54077
- #52 So. MS, .53360
- #55 Ohio, .52191
- #56 LaTech, .52000
That would be a WAY better conference than any of the G5 now, but it wouldn't even touch the weakest P5. Plus, remember that they built up those gaudy records playing mostly horrible teams in their weak conferences. If you lumped the best of them together each of their SoS would go up a LOT so it would be unlikely that they could maintain anywhere near that winning percentage.
Pods:
- Western: Boise, BYU, Fresno, Air Force
- SE: UCF, USF, So. MS, LaTech
- MAC: Toledo, No. IL, Ohio, Navy
- South: Houston, Troy, Marshall, Cincy
Navy, Marshall, and Cincy are obviously geographically misplaced but I had to stick each somewhere to make the example complete.
If I were tasked with "saving" 16 G5s from FCS relegation, I don't think I would go purely on recent results myself. Rather it would be a mix of recent results, markets, stadiums, recruiting, history, tradition etc. For instance I wouldn't "save" Navy and Air Force, while hanging Army out to dry. I would make room for all three.
Pods
Northeast: Army, Navy, Cincinnati, one of Temple/Toledo?
Southeast: Memphis, Tulane, one of Houston/SMUw?, one of UCF/USF?
Inland West: Boise, BYU, Air Force, UNLV
West Coast: Hawaii, Fresno, SDSU, oh I dunno... San Jose? Nevada?