Wrangled tags are probably a useful thing, but it would have to be all volunteer work to do, and we might have to import a tag cloud from somewhere like AO3 to get it to work effectively. And while that's certainly a possibility, I don't know how many users we would have to achieve tag wrangling on DW.

Community finding was the thing I kept seeing over and over again through the challenge. It seems like starting with a machine-generated index of communities is a good idea, except there are some communities that don't want to be found, so there would have to be some sort of opt-in, and it definitely sounds doable but not comprehensive.

The other way would be to try and keep a community with an index of communities and hope that everyone will drop by and leave communities to be indexed. That might go the way of other things, though, if nobody comes by or eventually there isn't enough support to keep it maintained.

Those both sound like good ways to start, though.