[rankelidyek]

I am also in the onlinewritingworkshop and won an editor's choice for a SF novel I'm writing (On Raven's Wings). For me, there is a reason they chose that first chapter. Smoothing out prose is simple enough. Watch sentence construction and swap phrases around. A larger problem I discovered a while back is the mechanism of a "hook". This may be where things are falling off (unless the concept of the story is not "marketable"). I feel you should always comb through and edit bit by bit, but it sounds like you should send out. Perfect your query (most important of all, sadly) and those first three paragraphs. The key to a hook is to give the mindset of your POV character. Often, a short, declarative statement is interesting and draws a reader in. Then, you reveal the thoughts behind the statement, what the character desires, then what opposes him (also works for a query). Afterward, then focus on setting and detail. I learned this by my usual method (called "the hard way") and have found that it works best for me since my strength is often bringing someone into a character's emotional frame of reference. Granted, there are other methods that can work for you as well, but this is tried and true.
Email me with any questions. I'm willing to look over the query--something that is nearly as difficult to fashion as the novel. You can also find me on the workshop. I run a couple critique groups and might be of some help. I'll look at the first chapter if you need.
There are others on the workshop who can help, I'm sure. Ruv Draba is a great crit. That said, it sounds to me like you can write. My suggestion is to get a great query, perfect the first three paragraphs then set it aside. Write another novel and keep writing. Often, the eye of the beholder is a bit blind at first. Once you sell one novel, the others may follow.
I hope this helps.