There are some sets of tags that are basically duplicates. For example:
It would be good to be able to notate such tags as synonyms, perhaps as a Tag-Tag relationship. It would also be good if tagging software could grab tags with a “total synonym count”, instead of just the tag count.
It would also be good to be able to mark one tag as the master tag of a group of perfect synonyms (likely what ever Wikipedia uses - “Drum and bass”, in this case), so that software knows which tag to use when tagging.