> but I'lll never want to randomly play the tracks of a novel, opera, or
> symphony

Hoi Henno -

You could set the properties for the playlist containing the tracks for a play to be "Play as single track" (I think) which is under the second tab of a playlist's properties (right click on playlist icon).

"Marking" a track is definitely a good idea - but I suspect it's a long way off.