I just finished Deaths End this morning so I'm experiencing that ponderous glow that you get after reading something thought provoking. Without going into spoilers, Death's End makes everything so... huge. It really made me feel tiny in our universe. These are good books with some flaws. You should read them.
> These are good books with some flaws. You should read them. Counter view-point: These are bad books with a few thought provoking ideas that are never explored, left behind to explore a ridiculous plot full of nonsensical actions taken by paper cutout characters chasing a political goals that also make no sense. Granted I didn't read the third book, but that's because I gave up not halfway through book 2. When I got…
I think this is the fundamental point where people like you who didn't enjoy the books and people like me who deeply did depart. I thought the unfolding scope of the trilogy felt like a logical, justified progression, in the manner of an escalating conflict. Yes it does escalate quickly, but there is a good reason at each scope level that it needs to expand to the next as the conflict spirals out of control and the technology involved improves. And in general I enjoy when things sort of escalate in scope like that, like Akira for instance. Maybe you prefer books that stay at the same scope the entire time but that's a personal preference.
Also I really don't see how the nature of the ending is at all akin to the "it was all a dream" type ending, because it doesn't fundamentally undercut that the things that happened actually did happen, and had consequences. Yes our assumptions about the nature of the fabric of reality are undercut, but not in a way that means that anything that we thought happened didn't actually happen or anything like that, and not in a way that undercuts stakes, if anything the stakes are far greater. And the choice to restart the universe so it can be better again is actually a deeply consequential action with a lot of seeks to it. Likewise I don't see how the larger scope of the later books makes the smaller scope of the earlier ones not meaningful? That's how we got here.
And I think more than enough interesting and unique speculative fiction ideas are introduced, and I think they are explored enough, in a grand and stunning enough fashion, to justify the book, even if they aren't perhaps looked into as deeply as you think they should be, despite the paper thin characters with nonsensical motivations. Especially since the actual political chess/information game between the trisolarans and humans is so interesting.