This forum is more about assisting ppl develop competencies than a turnkey forum.
Goal: Increasing Nixie life:
1) In that vein, all u have to do is incorporate a sampling routine on the switch to detect a long press or a short press. Use the long press for the set feature and the short press to permit a 10 second display.
2) Alternatively, you can code in a timed display on a duty cycle, perhaps 5 seconds out of every 20 sec for a 25% duty cycle and a 4x life on the nixie.
Either approach is not difficult but it requires some minor asm competence.