The ability to use a hardware button to go back a menu when you are in a sub-menu that is entered and navigated with the main encoder (for example when navigating plugin presets).
Touch screen aside, these menus are navigated using the main encoder. However in order to go back a level you have to use the back button on the touch screen. The minus button seems like an ideal candidate for this.
Reasoning: Currently the plus and minus buttons duplicate the function of the main encoder when navigating a menu. I would bet that for the majority of users the encoder is much more preferable for scrolling through long lists. Being able to use the minus button as a back button would streamline browsing with the hardware controls without necessitating the use of the touch screen at all, instead complementing the function of the main encoder. The button is already tied to menus so it should be trivial to change.
It could also exit a menu completely without having to make a selection. On the One and the Live it is easy to just touch the corner of the screen, on the X you need to move your hand off the encoder to do that - from what I can see in photos.
I can't think of what the plus button could be doing, so it could just duplicate the encoder's click in case someone finds it more comfortable than pressing the encoder.
This would apply to all MPC models as they all share the encoder and +/- button cluster. The user quoted below with a similar suggestion presumably refers to the MPC X. For users that prefer the current functionality, it could always be a setting in the preferences.
mpcchiq wrote:A back button for the user interface. Not meaning undo, but a button to go back on the screen.
Maybe we can use shift + left direction button
?
A lot of people seem to have no use for the +/- buttons. They have been there from the start, maybe now they can have this optional alternate functionality. I don't know how a universal back button would mesh with the MPC workflow, but a back button for menus would definitely be useful.