New champions
Can any new champion be automatically banned from ranked play (maybe only for any player under diamond but can be for all ranks) for the first 2 weeks or their release? these 2 weeks would at least allow for the champion to be tested in normals, rotating game modes and custom games in order to get a feel for them. Plus the second week after any new champion release is when they are in the FOTW meaning every player can test them out if they wanted to.