>I'd love to see some innovation with the old school design ethos too; maybe there are even better ways of displaying controls? Or maybe a new way to think about controls that weren't around back then.

Oh yeah, this is something we've been exploring (carefully) with SerenityOS! There's obviously been a lot of good UI/UX innovations since the late 90s, and it's super interesting to look for ways to integrate them with the classic aesthetics.

As an example, we use breadcrumb bars in our file manager, to display the current directory as a part of separately interactive segments.

And we also have "Assistant" which works similarly to macOS Spotlight, for fast access to a range of data providers.

I'm sure there are many similar concepts we have yet to discover :)