I'm now reading The Long Mars, and enjoying, though it leaves a vague unsatisfied aftertaste. I found the same with The Long Earth and The Long War; somehow, I want
more in the story.
The concept is most intriguing, and unfolds in a series of revelations that I enjoyed very much, but I feel like it's really just beginning, and that I'm only just getting to know the characters as the book ends.
Maybe because I so very much prefer loooooonnnnnng stories, that take the time to explore character detours and explorations of the environment. It feels like the Readers' Digest version, somehow.
I've been spoilt by some very long stories, I think, to the degree that when a story concept intrigues me (as this series does), then I want more depth and time and detail and colour and dialogue and thoughts and perspectives. More than a 300 page summary
.