We open up at +8.5 which seems high to me.
I agree, which leads me to wonder, what is home court generally worth to the odds-makers? Six? More? Less?
Typically around 3, but it can vary according to other factors.
Something to consider that is if in a normal-possession game, Ohio is perhaps 5 points better than Central Michigan, if the teams play at the same level for 120% of normal possessions, then Ohio would win by 6 points. Central Michigan's pace may add a point or so, good or bad, to its lines.
I agree, though, the line still seems big.