The Time Machine
I'd read this one many years ago, but it's short and easy to page through, so I gave it another turn. I'm glad I did. I remembered most of the main plot points - the Morlocks, the Eloi, their relationship, the machine itself - but not most of the language or Wells' final image of the dying Earth.
What I, as a modern reader, find missing from TTM is space travel. The whole theory on why the Eloi and Morlocks have become what they are is that man tamed the Earth, and then lack of challenge led to devolution. Not surprising, given that manned hot air balloons were pretty much the flight of the day. A more recent novel would have to work around the idea that man could turn to the stars for adventure and meaning when he's made the Earth into a garden.
final thought: Let's see. The science is still vague enough to be reasonable, in its way. The Morlocks are still creepy fuckers, the Eloi still pitiful, and the end of the world is still a depressingly bleak vision. I'm glad I reread it.