In my favorite college football game, NCAA Football 2004, I pick a team with a 1-star prestige rating (UTEP Minors), and build them year after year, only through simulation, attempting to create a national champion.
RULES: I am only allowed to improve the team during the off-season when recruiting incoming freshmen and transfers. I can manipulate the team's schedule each season, how I see fit. I can allow UTEP to join a new conference if offered, but I cannot switch teams. I can change the team's offensive and defensive strategy if I believe it will help win more games. I can manipulate the depth chart to make sure the best talent on the roster is starting. I cannot play any actual games. They all must be simulated.
This was a fun challenge. I'll likely try this again in the future with a different team.