That's not a great solution.

I'm not qualified to comment on the specific design aspects. But it's pretty obvious that there should be a path to repair that doesn't require involving you, for a variety of reasons, including that you are a finite resource, with a finite amount of time, and that you are not a commodity, but rather an irreplaceable human being who, like the rest of us, will one day no longer be available.

There are pins approaching a century in age, which are still being maintained in good, operable condition today. If the designers of those pins had taken as their primary means of maintenance the requirement that a failed part simply needed to be sent back to them for repair if anything went wrong, those pins would've been relegated to the junk heap decades ago.

Independent repairability is a must-have design goal for anything even a fraction the complexity of a pinball machine, but definitely for any parts in an actual pinball machine. Especially for new parts, where we now know just how long people will be keeping these machines around.

That's great to hear. There was some comment, not necessarily directed at your boards, above about use of PAL/CPLD/FPGA without documenting those circuits, making them essentially black boxes. That practice can create a situation where only the original manufacturer/designer of the board even has a hope of fixing it.

As long as your suggesting to send the board back to you is just that, and not because there's something on the board only you can repair or replace, that's fantastic. Being willing to service the board is awesome, as long as doing so isn't the only way to keep the board going.