In the Franchise Q&A these questions were answered.
Are teams adjusting schemes according to coaches?
Sadly, no. Playbooks are locked to teams and not coaches. So if Rex Ryan gets fired and goes to a 4-3 team the Jets will still run a 3-4 and Ryan's new team will run a 4-3.
Are plays being called according to coaches and players?
Play calling gets adjusted according to players. The CPU will adjust offensive playcalling to its highest rated offensive player. So if Drew Brees retires forthe Saints and their highest rated player is then a RB they will run the ball more in the future. I don't know if this has any effect on defense though.