I totally agree. One big issue is that many work on laptops and cannot / won't carry an ergo keyboard around.
The second best I found, besides having an ergo keyboard, is to use an actual japanese keyboard: laptops with japanese keyboard can easily be found / shipped. You can have a Mac laptop with a japanese keyboard, for example.
And thanks to the narrow spacebar on japanese keyboards and the additional modifiers, you get more modifiers and they're easier to reach.
So I use a japanese keyboard even though I'm not japanese.
Same!
It is pretty easy to build your own now as there are hot swap PCBs that don’t require soldering.
The worst part of having a small orthro board is staring at the hundred nice looking keycaps that have no home on your board after buying a set and putting on your base 48 keys.
I hear you about the keycaps. My solution to this is to just bulk order plain PBT keycaps so it doesn't feel as bad when you have spares, but it certainly doesn't look as good. It also kind sucks that not every profile works well with non-staggered layouts.
Still working on wrist pain though. I think I can attribute it to my slightly too high desk (which is unfortunately not adjustable).
That's why I like Mac keyboards. Cmd is right under your thumb. I did the same for my Linux machine, so win/alt/ctrl instead of ctrl/win/alt. It's a game changer and doesn't require any hardware modification.