I recently, on request, added an advanced settings. This allows you to disable some extra parts of GMPC.
You can disable:
- The disable album cover in the player part.
- Hide the favorite icon.
- Disable database, play-queue, search browser, tag based browser, playlist editor, metadata browser and now playing screen.
You can find it under preferences->interface:

Then you click advanced settings, you get a window with check-boxes. You might need to restart gmpc to fully apply the effects.

An example:

One comment
Nice change! Personally I usually use only two or three tabs. Another good thing in ui would be if view panes will be shown accordingly their usage frequency with the link to show them all, like it’s done for example in microsoft office.