I've also got problems with hidpi, but I'm using ubuntu 18.04 still. I was using the cinnamon desktop manager for a long time and I really liked it. It doesn't do anything weird like try to mac-ify your desktop like the default ubuntu desktop. However, sometime about 6 months ago it started "skipping" or pausing for about half a second every few minutes. I haven't been able to figure out what is causing that so I just switched back to xfce, which is fine, but not as nice. For example cinnamon would automatically change my resolution when I switched from the 4k laptop screen to my 1080p external monitor. I have to manually do it in xfce. But xfce lets me just disable the laptop screen when I connect external monitor so I just do that (I use it in clamshell mode most of the time).
Some things I really love about (my, ubuntu-based) linux on the desktop is focus-follow-mouse, alt-drag windows, configurable keyboard shortcuts (any keyboard shortcut, nothing is "reserved"), the way updates are handled, ease of software installation, the various available terminal emulators, etc. I really like the fact that xfce seems stable. Like on windows and mac things change all the time for no good reason. I think they do that with gnome as well but xfce, cinnamon are a lot more stable, feature-wise.
Some things I don't like about it: it's slower to boot up than my work mac. Performance, once running, also isn't quite as good (like programs take a bit longer to launch). Some features I use with mac/iphone aren't available (or I don't know about them), for example, airdrop to transfer photos from my phone to my computer, I use that a couple of times a week.
I would strongly recommend installing steam and playing Axiom Verge, it worked great on my linux laptop
But... oh yeah I had to install some external driver for my xbox one controller, and it seems to need reinstall when the kernel changes