I'll stand by my position that they weren't at any point a top 10 team in D2 this season. The GlIAC was way down with Wayne State and Saginaw Valley not playing to where most thought they would be. Ferris State blew their doors off once and beat them again during the season (which I think the 7 point loss is what many base GVSU on).
Here's my reasoning on why I don't think NCC would compete at the higher levels of D2. Talent.
NCC had a 2nd team all conference freshman guard this season. Throughout youth football and high school he was always a good player, he and my son were typically on all the same lists, fairly close to each other.
At a competitive D2 school, most freshman redshirt because they aren't getting on the field. There are two potential pro lineman on his team.
During their National title run, NCC had a d-back that didn't even play college football his freshman year and ended up starting the season and getting an interception in the National Title game
NCC has a freshman TE this season, that sees some garbage time in games, but was used sparingly in HS.
NCC could compete some weeks, but they will get blown out more than you think.