I appreciate you banning hackers, but keeping them on rankings after banning them is upsetting.
The ranking system is extremely flawed like that. Somebody can just make a new account and hack their way on the rankings for Arena/FM and the entire class is screwed because that person stays on the rankings. Imagine trying your hardest to get a good time and then boom a hacker appears and you know they're gonna get banned.. but they will still have their mark on that class and it's just upsetting.
Maybe have an employee look at the rankings once per day in the morning at server reset? I don't know what you can do to remove them from the rankings after you ban a hacker but please look into that.