I liked this rev's world painted map. However I feel it had too much water. Boat builds are indeed always beautiful, and I understand the desire for cool rivers, but these rivers were more like seas. Another drawback to a world painted map is lack of generated underground content, like caves and chasms. Edit- But we can just WE in caves and stuff. I guess WE'ing a sea for some boats is more difficult.
I think having a reductive vote to remove Creative Classic is a bit cruel. I don't use it myself but I appreciate those who do like it. Perhaps scale down the map to make room for other multiverses? I don't know the technicalities.
Perhaps the main overworld could be 'zoned' but not plotted, with cardinal roads going through. City zone, surburb zone, pixel zone, ancient antiquity zone (for castles, temples, ancient ruins), derp-zone (I've always thought a zone dedicated to extreme freestyle derp could be interesting), a parkour zone for various parkour maps. Perhaps the cardinal roads could reflect the theme for that zoned area. Roads change to city roads for city zone, rural roads for antiquity zones, derp roads for derp zones. This idea is a little rough because it has so much micro management. Perhaps have a very simple Cardinal spawn building with rules, then a freebuild 'derp' zone around it, then the cardinal roads lead out to the other themed zones scattered around the map.
Speedbuild contests are fantastic. Perhaps a similar institution for spleef could be arranged if there is interest. Spleef tournaments?
I'm also of the opinion to start the map as big as possible, if only because it will make the cartograph super pretty. With the expanding scheme, anything outside the initial parameter is not rendered in the cartograph. Although, previous cartographs did not have that bug? I do appreciate the optimized landuse the staggered expansion lends itself to though.
Schererer's slow build contest idea is cool. Perhaps there could be a 'warp of the month' deal, every two weeks or so a new warp is given honors in the server announcements.