SimLego:
I think there's no chance of using only one Adrino for all the tasks, even if the ports and the memory are sufficient. So this unit will handle three of the four instances where there just have to be delays.
I'll take you up on that challenge. Without knowing much about this particular pinball or driver board, it is much less demanding than - say - drive a 3D printer (3 steppermotors, LCD display, Serial I/O, monitoring switches, heatbeds etc.)
there just have to be delays
There is the Two LED without delay which shows you can have several, totally independent "delays" running, that is wait a short time, without using delay()