* Put the Dock left or right, vertical space is precious (trust me, do it for a week and then decide)
* Setup Hot-Corners (Settings -> Mission Control -> Hot Corners)
- Upper-Right Corner as Mission Control (Must be upper right so spaces are immediately shown)
- Lower-Left Corner as Application Windows
- just fling your mouse curser into the corner (use std. gestures on the trackpad)
This makes window management a lot better.* Maximise Windows by double clicking the Window title bar.
* Disable auto-{correction, capitalize, etc}, smart-quotes under Keyboard settings (if you want)
* Learn about the screenshot shortcuts CMD+shift+{3,4}, 3: full screen, 4: select area or switch to window select with hitting space bar once.
* Learn about CMD+space for launching apps
* Set Key-Repeat to fast and shorten the delay
* Disable spotlight for everything except what you want to use it for.
* Enable File-Vault
* Disable "Wake for Network Access" under Energy
* Enable the ssh server under Sharing "Remote Login" (If you want)
* Disable the visual/audible bell in the Terminal profile.
* Install MacPorts/Homebew
And one thing to internalize is that Apple is a little authoritarian about some UX aspects.
For example the snapping and window thing... Apple has a thing with continuos freedom opposed to the discretisation one is used to. I've come around to that view as well actually, free your mind, nature is not a stepped slider.
Cool Utilities:
MenuMeters with a CPU usage graph. this allows you to see if something is killing your battery.
MonitorControl (on github) to set brightness of external monitors.
LittleSnitch ($$) for fellow paranoid control freaks
IINA (github) best video player
UTM for VMs (free on github) paid options are good too
MacPass for KeePass databases
Hope it helps.