It is hard to find, most stats will only give you actual snap counts, not what type of snap did a QB take.
Did post a good article I found about the benefits being under center from the Arizona Cardinals, where our OC came from when he was their OL coach. They wanted Murray to be under center more to disguise what they were doing.
I did do a deep study on the Lions Offensive Scheme during last season as I thought Ben Johnson was going to be in consideration for the Cowboy HC Job. I think this is the offensive scheme the Cowboys want to implement:
-Marry up the run/passing games
-Have a two headed RB system; 1 power back, 1 explosive all-purpose
-Heavy play action passing game that is all set up by their run game