My own experience is that if you keep your screen on then that's where most of the significant power usage comes from, significantly reducing the usable life capacity of a single battery charge.
This refers to the auto-display-off time value (which I've set to OFF, so that the screen is always on... which is especially important to me while using the J3 in my car). It also includes extending the auto-off time value beyond the default 3-minutes.
But my own preference is that I LIKE seeing the screen, and album art, and being able to always touch the screen to control things. I don't want to have to regularly push the power button to re-activate the screen after every song, although I recognize that this may be perfectly acceptable for some situations (e.g. after launching a "favorites" or "playlist", and only caring about hearing the music set).
Consequences: (1) more frequent or regular overnight charges after significant self-powered use, (2) use AC-USB adapter when appropriate for extended use in the house, and (3) 12V-USB adapter for extended use in the car.