A very simple hidden feature: by turning off your Tecsun PL-880, then pressing and holding the number 8 on the keypad, you can turn on the PL-880 clock seconds display. Use the same process to toggle between settings.
Be warned that this free feature will not buy you extra time. (Sorry, couldn’t resist.)
You can follow all Tecsun PL-880 updates by bookmarking/checking this link.
A big question is whether the radio firmware can be upgraded by the user in the future to address some minor issues. Is there any indication of this? Can you maybe ask anon-co?
You mentioned the possibility of a hidden feature that would allow the zeroing of the display frequency when tuned to a standard (say WWV). Any news on this one? When a receiver can display a frequency to the nearest 10Hz, it would be nice to get it on the money.