One of my favorite and least favorite things about writing is the amount of drafts that accumulate, Sometimes I wish I could just write it once and be DONE. However...there is a beauty not to be surpassed in drafts. The first draft will always remain the most pure and most lovely part of the story. The first draft (if it doesn't bug me to death) is always my favorite version, untainted by anything it is perfect...until we let other people read it.
Spacing drafts can be very important, letting a manuscript sit for a few weeks before turning around and overhauling it for publication is important. Like other famous things like cheese...and wine (I wouldn't actually know about that one from personal experience but you know..) things get better with age. Leaving your lovely characters to sit for a few weeks in a dark drawer or a closed document allows you to look more optimistically and clearly about your story, also this preserves you from complete burn out.