As it has already been discussed before, the problem ratings in Chess Mentor don't really reflect the difficulty of the exercises.
While it's no big deal, maybe you could add an option for users to suggest a new (more realistic) rating to a problem they have already tried. Then from time to time, someone in chess.com staff could review the problems which have received enough rating suggestions (say 3 ?) and adjust the ratings if necessary.
It could be the same mechanism as is used for leaving comments on the Tactics Trainer.
As it has already been discussed before, the problem ratings in Chess Mentor don't really reflect the difficulty of the exercises.
While it's no big deal, maybe you could add an option for users to suggest a new (more realistic) rating to a problem they have already tried. Then from time to time, someone in chess.com staff could review the problems which have received enough rating suggestions (say 3 ?) and adjust the ratings if necessary.