My only suggestion to Ford would be to give the driver the ability choose between 2wd WITH rear locker engaged and 4wd.
Are you 100% sure this can't be done?
I only sat in one so far, did get to start it and mess with controls. I tried pulling the knob to engage the rear, it didn't work. I then pushed the middle of the 4x4 knob and it showed rear lockers engaged.