Who is the strongest non-helmet Big Ten program?
Likely between Wisconsin and Michigan State.
Without deep diving into the stats, the "feel" is that Wisconsin is more consistent, whereas Michigan State has a higher ceiling/lower floor.
Wisconsin is usually good for 8-10 wins, maybe 11 on a phenomenal year, and no worse than 5 or 6 wins on a really bad year.
Michigan State can rack up 11 wins and win/contend for a Big Ten Title on a good year, but then they'll have like a 3 or 4 win season.