I imagine something similar to steam's popular user defined tags.
updating the tags loses the ranked status, it could go with the initial tags to be set by the mapper, then the users can insert a tag on the beatmap page after the initial upload. if a tag is mentioned like X amount of times, it will be part of the beatmap page.
updating the tags loses the ranked status, it could go with the initial tags to be set by the mapper, then the users can insert a tag on the beatmap page after the initial upload. if a tag is mentioned like X amount of times, it will be part of the beatmap page.