Like Bender says, these buttons are so hard to press that there is no way that I'll hit them by accident. I'm not entirely convince that I like these buttons, but they may be just fine.
Bender, I will move the start buttons below the admin buttons.
I've rotated the thumb button lower than the last drawing. I may move it a bit farther away than it is from its nearest neighbor for comfort reasons.
I'm happy with the curved layout. This is about ergonomics for me, not about emulating what it used to be like. I use a split keyboard and a standing desk now, and I certainly didn't use those 20 years ago.

I'll finalize the function (and of course number) of admin buttons before doing a control panel overlay. I get the feeling that speedup could be a shifted button for me to use where no one else needs to really ever use it. The admin buttons for me are exactly what I want other folks to see to be able to get around when they use the machine without me having to help them.
Putting the admin buttons on the side isn't an option for the cabinet that this is going in (which I'm not going to modify).
I may still keep an enter key to keep the right-hand UI for getting around in the menus in one place. Also, button layout on different panels are going to be different, and I want to standardize on what's in the middle with the start and admin buttons.
I'm like to move from paper straight to thin plywood tonight so that we can get some playing in. I won't bother with any routing and will just topmount everything, so it sould be really fast (once I put my drill press together!

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