It would be amazing to have a keyboard with a “split” space bar, with two or more keys, like these keyboards have:
Unfortunately, a standard space bar woefully under-utilizes the thumbs. With two or more thumb keys you could use a thumb key for shift, backspace, or a layer switch key. You could use a keyboard layout that puts a frequently used letter like “e” on a thumb key. Lots of good options.
That said, ideally I would love to have an Atreus-style ergonomic keyboard on a laptop. But a split space bar would be next best and I think it would be an appealing and easy to adopt option for those who want to keep using the usual row-staggered keyboard.