Okay D&D has a huge number of tile sets from older editions. Fourth edition alone seems to have produced like a thousand different boxed tile sets. Thats a lot of great artwork going to waste and its even better quality imo then what most marketplace creators(Gabriel Pickard being the exception) currently put out. Since they tend to struggle with functionality and originality. (If any marketplace map makers are reading this and planning on releasing another forest pack. Make sure there is something distinct about it. Please.) So I suggest you re-release all the old tile sets. You don't even have to convert them for lighting and stuff, just scan and sell. Because as I learned the hard way, the old tile sets don't fit well in a scanner either. But I assume WoTC already has digital versions of the tiles somewhere. So bring all the old tilesets!