Your use case and mine, for example, are different. I generally am not a fan of playlists, personally. Occasionally, but not often, I'll want to listen to the same set of tracks again but more often I want a new mix every time. Worse than that, I don't know an hour from now what I'll want to listen to so I find that I generally can only fill out a playlist a couple songs at a time.

Since I need to manipulate my now playing often, having the ability to do so through vim would be basically godlike.

Now, if only it worked for a media player I actually used :/