The ability to see the coaching history of your OC, DC, and special teams coach would be nice. You could see if they were previously a head coach and that might give them better leadership abilities when coaching their particular unit. Also, coaching preferences would be nice and familarity with a particular formation. For example, June Jones with 15 years experience with Run 'N Shoot would be better than a coach with 1 year experience with the same offense.
Another suggestion would be that owners would pursue these coordinators for head coaching vacanies. For example, your DC has the number 1 rated defense in the league, and there are 5 coaching vacanies, hopefully, he would get a job in one of those spots. Reward the best coordinators with head coaching opportunities and the worst head coaches go unemployed or become coordinators then head coaches again, like Wade Phillips. There would be a cycle and at the age set in the game, 65, they would retire or if they did a horrible coordinator job, then they would go unemployed and after 2 seasons without a job, just retire.