You have to think of the Night's Dawn Trilogy, not as a trilogy, but as ONE book divided into three books (which are further divided into two parts each, to make it easier to hold the darn book while reading!). If you don't read them in order: YOU WILL BE TOTALLY LOST!! It really is one big long story arch, and it's not written so that you can just pick it up anywhere and be able to follow. Why would you want to do that anyway?! I've read some amazing scifi, and I have to say that Hamilton really is up there with Azimov and Brin. If you love them, you'll love Hamilton!
The best space opera I've read. His imagination is unparalleled.
Take 4 separate books, rip the last half of the pages from each and discard them, then assemble the first halves into a single book, using ten pages at a time from each, and there you have the perfect Peter F. Hamilton book. A series of unrelated, partial stories, in a convoluted mix is not my idea of good storytelling.