Alastair Reynolds 'Chasm City' is better written than 'Revelation Space' (though the first is still a thumping good space opera). I'm not certain whether or not it counts, though, not being a direct sequel.
Maybe a better example would be 'The Confusion' - the second book in Neal Stephenson's Baroque Cycle. It lacks the stylistic jumping about of 'Quicksilver' (which I enjoyed, but which kept breaking the sense of immersion), and has more 17th-century cryptography and bits getting chopped off.