It's funny, I did decide to read the books before watching the show. I'm about 6 episodes in and think it's very good. I think they actually improved the books in many ways.
I don't know if people just have a nostalgia for something they haven't read in a long time (sorry not having a go at you!) or they genuinely like some really not-great aspects of the books that are a victim of their time.
The fact they changed a bunch of characters genders actually works - too many crusty old white (assuming) dudes that doesn't work nowadays. Making Gaal a more rounded character to tell a story they apparently write in the book makes a lot more sense.
Its not FOSS but if you need a work alterative to GIMP I use Photopea a lot. Works as a PWA too.
I've been using design software for over 25 years; Photoshop has been there for the majority but I've often tried coming back to GIMP here and there, but it's never grabbed me in a useable way.