I think Peter F. Hamilton is a hack, but he's an entertaining hack all the same. Misspent Youth is probably his weakest book. The Mandel books are indeed a lot of fun, so long as you don't take them too seriously. The Night's Dawn Trilogy is also fun (how about a \
zombie bodysnatching Al Capone in space, anyone?). Or for other gothy SF, check out Alastair Reynolds, though he's also a bit of a hack!

I rather prefer Greg Bear's loosely connected series Queen of Angels/Slant/Heads/Moving Mars. But if you want the *really* good stuff, go for Iain M. Banks any time. Pick anything -- they are all consistently good, but the Culture series is superb. My personal favourite is (non-Culture) Against a Dark Background.