I'm forced to use that shit at work.
For window management "Rectangle" helps.
For a better tabbing behaviour I use "AltTab".
For setting the volume of a sound device over HDMI I can recommend "MonitorControl".
Then edit the keymap to be less stupid with Ukelele, use ForkLift instead of Finder, qView instead of Preview for photos, and of course Firefox instead of Safari, and things start getting tolerable.