I'm using MS Natural 4000 with a Macbook. Alt and Win keys are remapped through the standard settings, the context menu key is remapped with Karabiner. Some extra keys can be mapped, only alas the numbered ones aren't seen even by USB Overdrive.

(Of course, the Natural/Sculpt series barely scrapes the ‘ergonomics,’ what with the slanted key layout inherited from typewriters, the flat board made for extendable fingers instead of jointed ones, the too-low wrist pad.)

As for the special keys, I'm not sure what that's about, since I'm using pretty much the same number of hotkeys as I did in Linux and a bit more than in Windows. I'm also using Alfred for many commands, which are made in English instead of obscure semi-random keys.

One of my most favorite things on MacOS is that cod+? Opens the help search menu which you can use to type the name of a command you want to run but don’t know where to find or what combo it uses. It’s especially useful for menu items that don’t have a key map assigned.

What? They don't want you to know them by heart that's why they're all listed in the menu next to every command that has them and they update live as you hold down the keys so you can see what modifiers are available.

Also, you can use whatever keyboard you want. I don't see how this is an issue at all... And what microscopic return key are you referring to? The return key on my MacBook is nearly the same size (maybe a half-centimeter shorter) than my full-size desktop keyboard.

I use a MicroSoft ergonomic keyboard with my Mac Pro. It works just fine. I also have all of my keys mapped to the same as what I was used to when I used to use Windows (ironically the last time I used Windows was about 15 years ago, old habits die hard).