For me the top 3 issues with LS are as follows:
1. Cant apply covert art from a locally connected client. This means I have to remote desktop into my server every time I want to apply a movie poster or album art to a new file. I set MC to use a folder to keep the cover art in, and so it should be simple for a LS client to save cover art to that same location, if it can resolve it.
2. LS client doesnt sync back which view I was last in. I often do big tasks on the server and so I finish up on a "Tagging" view. Then when I connect with a client I always start up in that same tagging view. I'd like to be able to start up where I left off, no matter what computer I was using previously.
3. Library Tools are dangerous. I think they should be greyed out and unusable in LS clients. If I do a renaming or moving operation on files with a LS client, and the server is set to auto-import, then it finds the files and reimports them. This totally screws with the "Recently imported" playlists and sorted lists.
I would also love to be able to edit viewschemes in a client, but understand that that might be the last thing to be added to LS.