Another low priority “nice to have”.
Assuming “Continuous Playback” is off, when a track is finished, by hitting play you start listening to the next track in the Queue. If there are no more, nothing happens. Perfect. However, you may not have started listening from the first track in the queue, thus once you listen to the last in the queue there are still tracks left at the top. The widget also shows No Media even though there are.
I suggest that once the last track is finished the pointer goes to the top of the queue, so if you decide to continue listening, by hitting play you will hear the top of the remaining tracks, if they exist.