Ok, after getting inspired by a conversation with @algernon earlier today (and their related blog post), I've decided to try out life without syntax highlighting.
I'm not sure how long I'll stick with it, but I've changed out my color scheme—so at least I'll have something new for #screenshotSunday this week.
(I'm using the #noFrils syntax theme, ("the theme for vim with so few frills we got ride of the extra L!")) https://www.robertmelton.com/posts/syntax-highlighting-off/