Well that settles that, then.
Filling-in-the-gaps-books wise, it's hard to do better than Earthsea in my mind. They're quite short books, yet I found myself far more engrossed in the world and the goings-on than some thousand page Sanderson tomb I snoozed through.
But a big part of the problem is that after looking into space colonisation etc a bit, the aliens in most alien invasion stories feel utterly stupid to me.
I can still live with 'War of the worlds': their aliens only come from Mars not from the stars, and I can suspend my disbelief over eg its theory of how the planets formed: it's just a fantasy world where outer planets formed earlier and are older.
But the Three Body Problem tries to be current-ish with modern technology. And its aliens have enough technology to just build orbitals or terraform Mars or so. Or just kill off all the humans from space with an orbital bombardment or a killer virus. Instead of whatever clunky and ineffective methods they use in the book.
I did like the start though, when things were still kept behind the curtain. Also the Cultural Revolution flashbacks, too.
War of the Worlds never lifts that curtain for sure. Everything stays fairly mysterious, and the narrative only gives us some limited speculation from the narrator who clearly has also only a limited view on things.
Interestingly this section either appeared in the beginning or somewhere in the middle depending on the translation/version (I forget how the distinction was made) due to it being so different from the rest of the book.
It was in the beginning when I read it years ago and I think it took a bit for its context to make sense but I also read many lost interest during it.
I enjoyed all the books. (spoilers incoming) I actually enjoyed the love story elements, how a star given to someone would play such an important role later. How he survived in the end and communicated the three fairy tales, and enjoyed each in turn. I've never seen a story span such a vast amount of time nor remember one that took us literally to the end.
Per the parent comment, it does a lot with very little. And it's heady and literary and beautiful. Not everyone is into that. But a lot of people are.
They feel juvenile, trying SO hard. Using a different person perspective in one of them to hamfisted effect, as opposed to someone like Tamsyn Muir who integrates that device for good reason and to brilliant effect.
I gave NK a solid try and was appalled at how in the world anyone could think these are engaging.
The combination is fantastically human.
The popularity of that book along with stuff like N.K. Jemisin winning "Best SciFi book" of the year 3 years in a row prove more than ever that the vast majority of people simply don't have taste in the sense they can not decide if they actually like something or not they can only like what other people like.
That book was objectively bad but it keeps showing up on the top of best sci-fi book lists for some reason and so a lot of people keep (mistakingly) thinking they liked it.