Great work and research.  I reckon my lesson here is that Pro Football pays well enough and wants only players who have played at the level of intensity you find in D 1.  The smaller conferences can turn out skillful players, but the Pros have to question the desire of the products of smaller programs. 

I am sure the famous Joe Green from North Texas expected to land in a bigger college, but he did ok.  And N. Texas is D1 and seems to be getting roundly thumped, so they are no better in most football fans' eyes than a lot of D3 teams.  I bet there are a lot of pro players from small schools.