I love niri but will use kde again if needed, if niri doesnt work well on OMLx I will still enjoy OMLx (I love the work and community the devs and volunteers have made here)
if you are using niri, how easy or hard was it to set up on OMLx?
Bonus question: anyone tried Dank Material shell or Noctallia shell with hyprland or niri on OMLx?
Without messing with your local installation, you can test niri via a Live USB. It was easy to setup, and I did not try those other options you mentioned.
Just grab a version with any desktop and install niri from there as a test run emulating a ‘clean’ install. After installing, I would recommend updating the config first then logout, select niri as the desktop and relogin.
I tried this from the LXQT live usb for minimal interference from other settings. At the end of the day it comes down to your preferences. It works as intended and YMMV, although I did have some crashes from the cooker version.