Icon mark
I've quite a lot of rare ROMs from systems not yet emulated. These obviously don't work but it's nice to have them in the system menu with the ability to browse the games and look at the info on them even though I can't play them. Would it be possible to add a "mark" feature to individual icons at either system and/or game level with something like a small superimpossed cross or tick. It would act as a nice quick reference for the user to mean whatever they want. Personally I would put a little cross on systems or games that I knew did not work. Something like this:
