My biggest complaint is when other authors take over a story with an established character. They *never* portray the character the same way.
Collaborated works are okay; except for the blaring changes in writing style as the story switches from one author to another.
With Sci-Fi I think the fault is trying to describe every little detail of something rather than just the concept. A reader can construct your vision in his mind with just a few details; he really doesn't need to know that tab A fits into slot B (or in this case, that the curve of the aperture was offset only by the oddly mechanical tubing connected to the posterior housing unit...).
I guess the only other complaint I'd have about Sci-Fi is that many times the authors get so caught up in the world that they forget the characters. By the end of the story the plot has worked itself out and you still don't know why something happened, simply because the author didn't flush out the key players well enough.
Good luck, Fly! I've written a fantasy novel and it's been sitting and collecting dust for well over 10 years. Never even tried to send it to a publisher, it was enough for me just to finish it.
