...on the number of assistants and analysts you can have on staff. Heck, I'd put a team of experts together to focus on very specific aspects of the position (game prep/film review, technical work on mechanics, analyzing areas of improvement, etc) and have guys like John Beck on retainer for the off-season.
I heard rumors from Ute fans complaining that Isaac Wilson didn't like to do film study etc (not sure if that's true or not) but I'd basically make being the QB1 a full time job or make it like a degree and give him a variety of workshops to do that focus on specific elements of the QB position and then grade him on his progress. Wouldn't leave it up to him to work on improving.