I don't think there are a ton of available graphics that are ripped from copyrighted sources for people to upload. If graphic artists are making their inspired works too obvious, then we need to start there and make it clear that none of their work will be of use to the game.

Also, I agree that the system should be reworked but since it doesn't sound like that isn't going to happen, then maybe make a small adjustment and get rid of permanent bans or put a PERSON in charge of graphics ban appeals.