-- Yes, the edits will make your story different. That would be the reason for the edits.
-- Sentence fragments, run-on sentences, and comma splices are not part of your "voice." They're grammatical errors. Fixing them will not substantially change your voice. This is what line edits are for.
-- Why are you shopping your book to us when you have a publisher you usually use? If it's because you think the story is a good fit for us, rather than the usual publisher, that makes sense. But if you're here because this is a genre you've never written before and then you resist working or promoing with us because your usual publisher doesn't do things the way we do... don't be surprised if your sales with us don't do well. You're a new author to our readers and your regular readers need to know this book is as killer as your "usual" books. Really.
-- Even if you’re sure your editors don't know as much as your beta readers, do what the editor wants anyhow. Our editors get paid to make it work for a market. Our market. They may get bonuses if it does well. They actually have an incentive to make it sell better. Your beta readers don't.
-- If you don't meet your deadlines, don't be surprised if your book doesn't release at the date you promised everyone it would.
-- Most authors can write books. Very few can also write good blurbs. This is why we have marketing people -- to save authors from themselves. Sometimes the blurbs emphasize things you don’t think are important. But it might be important to readers when they decide to buy.
-- Happy editors are easier to work with for your next book. In fact, they're there to make sure there is a next book.
Treva Harte (with contributions from Margaret Riley of Changeling Press)
EiC, Loose Id