I agree with others about keeping things fresh is best achieved by participating in online leagues and clubs. They can offer some of the best competitive virtual racing you can experience. Practicing and doing setup time trials for organized races to get ready for the main events are a good fun also. Leagues can offer full grids of similarly skilled racers to race against that will have your heart racing and your knuckles white, how can you get bored with that?
A sample of just one out there, how can you not want to experience something like this?