OK, so this is actually a suggestion for two connected challenges, with a reasonably simple concept:

Month 1: the challenge is to make a map, any style/subject, but with several key features left out--e.g. if it is an overland map, include only natural features (mountains, rivers, forests), but no labels, settlements, important sites; a city map can only include street layout, and not buildings etc.

Voting decides which is best, as usual.

Month 2: the winning map (or maps, in case of a draw) from the previous month are provided, and entrants to this challenge must finish it (or, if there are multiple, select one to finish)--i.e. add the labels, settlements, important sites etc.

THW