I've always wondered why the original Wonderboy, be it Arcade or Sega conversion and of course Adventure Island wasn't mapped. The games are difficult. There are a lot of the same BG designs in the game like in the forests and it could also get confusing.
Mapping Adventure Island should be easy enough considering there are Genie codes for it to help out. But not for Master system. As far as I know. I already have area1 round 1 of AI almost done. I've figured out a trick to map it quite easily, but time consuming since I'd basically redraw the map using tileset images.
As far as Wonderboy goes there are over 36 areas to map at least ; 9 areas, 4 rounds each = 36 in that game not counting the secret bonus levels. And each level is pretty long. About 8196 pixels. (at 8196x224)
At any rate. This game series is very nice.