I do the same as well and then make coverage Playmakers based on the formation.....I have good not great D...
I see that making it so that the AI jumps routes based on how many times you run them is a cop out and shouldnt be in the game....
EX: I just learned alot of route combos that REAL nfl teams use every game and added them into my game.....
They will run lets say a curl flats combo on the backside of the formation all the while running a totally diff route combo on the other side....they will do this every play. run curl flats on the backside and run whatever on the other.......
so If i keep running curl flats on the backside and Diff stuff on the other is it fair that the AI can jump that play just bc I run curl flats combo alot on the backside........It should be up to the playcaller to make changes. this separates the good players from the rest imo