I've been using Audacious together with its last.fm scrobbler plugin for a long time, but only recently I have realized that the plugin doesn't submit album artist information to last.fm, even if that information is present in audio files' metadata. last.fm accepts album artist data in scrobbles: https://www.last.fm/api/show/track.scrobble
I examined the source code of the plugin, and it looks like it's possible to add album artist support. If there is any interest or demand for such functionality (or at least no opposition against adding it) then I'm willing to work on it. Please let me know.