I'm guessing this is mostly up to Buzzmusic, who I don't think I've ever really seen online, especially recently, but it'd be cool if the LE had it's own music, or at least allowed you to switch away from Piano/Electroforte. The first idea is definitely a stretch but I feel like the second idea should really be implemented imo
Just in case you didn't know, the level editor uses the same music as the menus outside of levels. It can be changed by opening platinum/client/mbpPrefs.cs and changing this line. Replace the song's file name with an asterisk to have it choose a random one. The quotes are of course mandatory.
$pref::Music::SongsMenu = "Electroforte.ogg";
There isn't a setting specifically for the editor though. You can also temporarily change the music playing from anywhere in the game with Ctrl + F5 which opens the jukebox.