What are you calling the sequel? Ender's Shadow or Speaker for the dead? If you're referring to Ender's Shadow it's not a sequel but the Shadow series which follows the Ender's Game story from Bean's perspective. If you're talking about Speaker for the dead it is the true sequel but rather dry and a difficult read. Once you get into the next two books they actually get interesting in my point of view at least. Ender's Shadow is also quite good, I personally preferred the Shadow series over the original.
There is also now the first formac war which tells the story of when the buggers first came to Earth for the first war and the 3rd and last book in the trilogy was just released not long ago and the two I've read so far are good.
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Pretty much anything by Peter Hamilton. very good writer, the only real producer of true space operas nowadays.