Recently, Gelbooru (and a few lesser boorus before it) has switched to using futa counters (1futa, 2futas, etc) for futanari characters in place of 1girl. Is there a possibility of Danbooru following suit? I understand it would be a pretty big change, but it could be done with a few mass updates, and Gelbooru seems to have implement it well.
Something like 1girl+solo+futanari -> -1girl+1futa and 2girls+futa_with_female -> -2girls -multiple_girls+1futa+1girl (and similar ones) would take care of a vast majority of futanari posts. Higher complexity would require manual tagging to count individual futas in a picture, however.