pic handling for indexed items

[aliasname]

Using pics for 'real' folders is pretty easy since Minim either allows collecting embedded art or picture files places in the physical folders themselves.
This works as long as you dig down a straight path or in case you want to deal at file level.
if you want to index for label/publisher or /country/language I'm lost, since I can't find a way to tell Minimserver that a given publisher name should be served with a picture belonging to that publisher.
I've tried a lot with playlists and such like without any luck.
Means I tried to build a playlist named 'Virgin' so that this acts as a publisher index but I didn't get it working.

Any idea if there's a way to get this solved?
If not, any idea if something could get implemented some day allowing that?
Applies to multiple uses. Genres, Publishers, Languages, Releastypes, Decades whatsoever, in fact everything which lacks the presence of physical folders.