I haven’t done a deep dive but I can’t help but think having a very strong road record hurts your home ranking in this. If an awful team never wins on the road but only drops a few at home that will very much inflate the home effect compared to teams that travel really well and still only drop a few at home. There is not as clear a performance gap between home and away which honestly is a good thing.
RE: This, I was mostly going off of my perception that we were especially strong on the road in the (post-rebuild) Underwood Era, but I wanted to look back at our Big Ten road record in past seasons where we finished in the top 25 (i.e., removing the dud years from the equation). I put our final AP Poll rank at the end of conference play in there as a general point of reference for what caliber of team we had that year.
16 CONFERENCE GAMES
2000: 4-4 (.500) ... #21
2001: 5-3 (.625) ... #4
2002: 4-4 (.500) ... #10
2003: 3-5 (.375) ... #13
2004: 6-2 (.750) ... #12
2005: 7-1 (.875) ... #1
2006: 4-4 (.500) ... #9
20 CONFERENCE GAMES
2020: 5-5 (.500) ... #21
2021: 8-2 (.800) ... #2
2022: 7-3 (.700) ... #16
2024: 6-4 (.600) ... #13
2025: 3-2 (.600) so far ... #18
So it definitely seems like when you hold other things constant (say, a ranking in the teens of the top 25), we are definitely much better on the road these days and unfortunately also less dominant at home. I think what also helps this perception is that some of our most memorable wins these past five seasons have come away from Champaign:
2020
W 71-70 at Wisconsin (broke our losing streak vs. them and began our hot streak)
W 64-62 at Michigan (Ayo buzzer beater)
W 62-56 at #9 Penn State (statement win to break a 4-game losing streak)
2021
W 74-69 at #23 Wisconsin (first challenge without Ayo)
W 76-53 at #2 Michigan (insanely loud statement win, again without Ayo)
W 73-68 at #7 Ohio State (third straight game on the road, Ayo's return with the mask)
2022
W 74-57 at Indiana (hugely hyped Saturday game for them on ESPN, and we whooped 'em)
W 79-74 at #19 Michigan State (clutch ice shot down the stretch from Trent)
2024
W 76-58 at Rutgers (first win of note and shocking dominance in a game everyone expected to be close)
W 85-80 at Maryland (finally beat them in a thrilling finish)
W 91-83 at Wisconsin (systematically beat them when they BADLY needed a win)
W 73-61 at Iowa (absolutely dominated them from start to finish when their NCAAT lives were on the line)
2025
W 109-77 at #9 Oregon (need I say any more??)
W 94-69 at Indiana (setting embarrassing Assembly Hall records, lol)