So essentially we are better off merging some tilesets that are small, like the YI and the NSMB tileset? Since they take up more memory to have them separate and they are just small at this time.
My favorite tilesets are the SMAS and the modified tiles from those. Ones like extra colors. I am making more tiles to fill up the SMB tileset. That includes tiles that had a different appearance in the 8-bit versions of the games than the SMAS games that were created later.
But most of all, I want to let people be creative with this game. With tilesets with many colors or tile appearances it lets people create what they dream. Tilesets like YI or the misc are alright to be in an expanded tile pack. But I think the tilesets (including my recolors and edits) that fit with SMB, SMB2, SMB3, and SMWorld should stick with the main download for this game.