you could still do something like that by artificially holding your players to some set standard gpa once they are in. for instance 4.6 or something. or strive to have the highest gpa in d3. but to do that, youd be at a serious competitive disadvantage. but the same would be true of your original idea.
Im not sure why you see this as a flaw, etta
even if there were more high gpa kids, they would either be weaker players
or else they would be in high demand and more difficult to get. and or become d2 recruits.