@Flophouse_Sam Zettlr might be worth a peek (https://www.zettlr.com/)
I like LyX's WYSIWYM (what you see is what you mean) approach, so you're not faffing around too much thinking about formatting.
I use emacs for writing (as well as coding), but probably wouldn't recommend it off the bat. It took a wee bit of config to get it to be a nice word processing experience for me. But I do love it, so I persevered.
Kind of sad LibreOffice doesn't seem to have a dark mode.