Hi all,
I went through the data and put together a recap on what NCAA Football teams were "over" and "under" rated this season according to how they performed against the spread.

Link is here: College Football ATS Performance

For those that want the short answers:

Most overrated
1. Akron
2. UMass
3. NC State

Most underrated
1. Ohio State
2. Central Michigan
3. Louisiana Lafayette

I am a data analyst in my day job so the post has lots of interactive visualizations. Note that the data only goes through the regular season, so it won't include conference championship games and bowl games. Let me know what you think!