PFF mainly. They got Average Depth of Target and Yards per Route Run. Can calculate Target Share, Target Rate, and Yards per Team Pass Attempt with their targets, routes, and pass attempts too. (Now if someone missed a lot of games you’d have to calculate TShare and YPTPA in only games played).
Theres other resources too you just need target and route data
I’ll also plug a friend.
www.dynastyIM.com
It’s a fantasy source but still really informative and has all these and more already calculated for college offense skill pos.