Dark Reader extension does basically this (I think they either change colors or add the invert filter depending on what looks better?), but also has builtin CSS override rules for many sites. Love it.
Sure. I prefer to minimize depending on more extensions (for futureproof-ness, performance, security). These days, { uBlock Origin, Vimium } is all I need :)
That's a nice approach! I try to maintain a practical balance here, my extension list is basically: GreaseMonkey, Stylus, uBlock Origin, Consent-o-Matic, Dark Reader and maybe a couple more.
In theory, one can use uBlock0 for everything (with CSS and I think also JS injection), but userstyles and userscripts are way easier to use sometimes. And you can reimplement Dark Reader with userstyles, but you'll have to keep track of various site-specific tweaks to make it look good. (Should be possible though! Might be a cool idea for a pet project.)
But I understand the concerns with having too many extensions from too many different authors, yeah.
