How about this: give it a score-reducing effect.If we have a score reducing affect it would totally have my support
i.e. users have an option every time they play a map, to either:
1. Play it with mapper's AR, and score on it normally
2. Pick their own AR, and then score is reduced to 50% similar to EasyMod, except without an effect on circle size etc, and with letting you pick /any/ AR you want.
Also, it would be nice if there was a bigger range indeed. Instead of just 0-10 with 1x increments, 0-11 with 0.33x increments, so that you can pick 9.3, 9.6, 10, 10.3, 10.6, that would be great. It would be a fun option that people can use similar to EasyMod today without worrying about how this affects ranking. Sure, you'd be able to top-score with an AR of your choice, but lets be realistic it's not that hard to read mapper-default AR and a 50% reduction won't make this mode a popular scoring method; thus I'll be just an option for fun. I'd suggest making it unranked but since the current stance is against unranked plays, ranked with reduced score seems like the best compromise... or to put it shortly, it's win-win. You can play with whatever AR you want if you just play for fun, or you have to accept the mapper AR as part of the map difficulty when you're playing for score.
This is reasonable isn't it?