I'm a decent consumer of map tiles and other things on the marketplace as I am not artistic in the slightest. It would be great if map tiles could be automatically sized when I drag/drop them onto my map page. It would just be a huge time saver, and since most authors include the tile size in the name of the tile, I can't imagine it would be the hardest thing to implement.
If you hold alt as you are dragging an image it should keep it's resolution (up to a 3x3 square). Not sure if this helps but it's certainly not common knowledge.