Mostly I use Geany, which is a pretty straightforward, but also pretty powerful text editor. It has nice things like column selection, tabs, and a built in terminal emulator. If you're familiar with Windows it's kinda like Notepad++.
I guess QOwnNotes counts too! Which I use a lot for organising notes. I always have it open.
I really enjoy learning about interesting Vim features and have romantic ideas about learning GNU Emacs (especially org-mode and Acme, but that's more just out of interest than any practical need or want for efficiency.
These are the features I look for in a text editor:
Ones I don't really care about: