A few areas which could be improved:
1 - Finer grain control of scrapers and where they fill in. I noticed that thegamesdb often has nice fanart, but their game descriptions and screenshots are often lacking compared to that which is available on mobygames. It would be great if I could tell the importer to grab fanart from thegamesdb, covers from mobygames, and descriptions from wherever.
2 - When editing boxart, screenshots, fanart, etc, it would be really useful if we could drag image files from windows explorer onto the emulators2 window and have it set the art that way. currently i am forced to right click the area in emulators2 config, select "show in explorer" and then drag into the folder and rename the jpg accordingly by hand.