If you are going to spend this much time on ergo keyboards, please just learn Dvorak. The comfort improvement alone is one reason (of many) to switch.
Please note that I'm not saying people shouldn't ditch QWERTY. They should. But that alone isn't enough to just declare the battle won and go home.
(While the keyboard.io prototypes are labeled in QWERTY, the firmware speaks Dvorak and Colemak as well. As of last weekend, it also speaks Workman and a variant of the Maltron layout.)
The difference is more like using an off-road bicycle to travel on flat roads. It's just the wrong tool for the job. The standard keyboard layout was designed how it is for a specific purpose: to allow physical parts to move on old typewriters. The placement of keys serves little purpose to the typist.
In our collective madness though, we have adapted ourselves to typewriter layouts, rather than adapting the layout to fit our hands when the requirement for moving physical parts disappeared.
The higher price of ergo keyboards is mainly a consequence of a much smaller market. Standard keyboards are only so cheap because they're mass produced, and have had countless iterations to simplify the production process over the years.
I'm in desperate need of a better ergo keyboard and I find projects like this one fascinating. I tried designing one myself a while back, but I don't have the skills to make it happen.
On a Scandinavian keyboard I also put esc on the extra key right of the left shift. My current laptop has a US keyboard but I'll be a smarter shopper next time.