I don't know if this is a majority opinion but I'd say Duluth is clearly a rival based just on the past 15 years.
Plenty of Gopher fans are angry about Duluth winning the majority of the matchups in the past 10 years. I mean I think the Gophs are like 3-13-2 against them in the past ten years...
BU and BC are loaded but have they won anything lately? UMD went to 4 straight Frozen Fours and they didn't have out of this world recruiting any of those years. Recruits aren't everything.
That is the definition of a talent gap lol. Just can't execute at the rate UNC is so far.
Case in point, a talented team puts it in the end zone after that INT