Comments/Ratings for a Single Item

I just had an idea based on a game of heavy gravity chess I'm playing with Vitya Makov. Vitya told me via the comments that he wanted to be able to play with castling. This had me thinking; is it possible to add a way to make notes to games when making them? Because I figure it is easier to be able to say "this is heavy gravity, but castling is allowed" or "this is shatranj, but let's play with a two pawn step" or whatever. Given we do play variants, I figure it may be helpful rather than having to start a game up before being able to talk to the opponent to present any house rules you want.  And it could maybe be put somewhere near the time controls when you go to accept a game. This way the person who wants to play with such changes will be able to play them without running into people who do not like it, and people who don't wish to play that way won't accept a game and then find out there are changes they may not like.

This isn't a knock, by the way. I actually liked Vitya's idea a lot and I figured this would make it even easier to be able to play a game with small tweaks, and be upfront so that both parties are aware of the tweaked variant that is to be played.