Hi,
Should we try allowing image upload for Advanced Level Editor? Most probably it will be with premoderation either by staff team or voting from some of best map makers.
It could support features such as choosing layer on which image will appear, ability to upload transparent images and generally be manipulated with level logic identically to decorations. Additionally it could also have size limits of something around 2000 x 2000 px and file size limit up to 10 Mb.
From what it seems like - it could be used as foreground & background custom level designs, interfaces, custom entities, slideshows etc.
It could also be good to double check each upload for being an original work. I think it can be possible too, though manually.
What are your opinions?