Just don't do anything to upset the virtual players' union, such as doing away with the options system. They can be pretty nasty once you get them riled up.
PS - As a general rule, I don't "cheat," because I find knowing I needed to do something underhanded to win takes away from the experience. However, I have unretired a couple of players in the past in my main solo league - the "house rule" is that they can't be on my team, and it was only for the express intent of reaching some career stat goal.
PPS - This first came up when a pitcher retired with 298 wins, and I decided that just wasn't right.