Karabiner is incredible for making keyboard shortcut to do some pretty complicated task.
Obsidian, what a note-taking app! Makes Evernote looks like a dinasour.
Vim (and NeoVim), you learn it once and use it for everything.
I am using Joplin: https://joplinapp.org
Using Dropbox as sync with E2EE (but you can use other ways to sync)