Take a look at my response[1] from a couple of weeks ago to a similar question on HN.
The tl;dr is to use Plasma Desktop, take advantage of its ability to create keyboard shortcuts for everything, and use Plasmoids to create a global menu and dock.
I didn't mention it in the post, but KDE Connect[2] works on most desktop environments and integrates with tablets, phones and other computers, and it's great.
There's sandbox info in the parent post[3], if you need a sandboxd replacement, too.
[1] https://news.ycombinator.com/item?id=23473207
Thanks for these suggestions, I will be returning to linuxland after over a decade away.
No problem. Check out r/unixporn and r/kde on Reddit, too, there seems to be a trend of some users mimicking macOS flows on there.