Have I got enough pins in my Uno or should I use another board...?

I make PCBs. Others use Uno for development, then use a Promini in the design in place of the Uno.
Just making 1 of these? Maybe just wire one up on perfboard.
Here is Arduino functionality at lower left, with some custom circuitry around it,
and an adapter board to make a circuit easy to duplicate & use, in this case a MAX7219 for LEDs.