Everyone loves a basemap, why not run a basemap minicompo?
They are fast and fun to make, and knowing you don't have to add much fine detail to the map makes it that much easier to join in.
The winner's map could be made into an official TWHL basemap compo, OR perhaps any the entries to the minicompo could be chosen to enter in the official contest.
If you wanted to go crazy, each basemap entry could then be used for a subsequent minicompo. Just spitballing here; there are a lot of directions we could take this, also with prizes and whatnot..
Would anyone else be interested in something like this?
Note
I would also recommend Vanilla HL entries only for simplicity, fairness, and ease to link them all together for a mappack/preview(ala cubicles).