As for where I am...
I'm done. I've killed all the darlings I can face killing. I am considering another boxing for a couple of weeks to read one last time. I worry that my pacy end might be interpreted as me suddenly getting bored and rushing to get it done... or that the pace will be seen as uneven. All of it was a choice on my part and I fully plan to revisit some sections in flashbacks within the sequel.
In terms of worrying about chopping the good stuff, I might not be the right person to comment; I spent £2.75 submitting the above crappy Dead Cat poem and thought nothing of it. I think though it is a bit like the clean up or decision advice - imagine you've done it, is it missed. Steak or pork? Have someone decide for you, if you are upset with the decision then you know to go for the other. Keep old versions, chop and see. Does it still inform your character?
I've always thought of it as the Star Wars method of editing and now I've had to do it on the big scale I really, really believe that it is true:
A New Hope was incredible. We arrived in the middle of action with very little in the way of introductions to characters or the situation. The story was underway, every single character we met seemed to be living their own film that started long before this tale and would continue long after it. We just knew that there were pages and pages not shown that fleshed out the history the politics, the relationships... even the props all looked like they'd lived a life we knew nothing of.
Phantom Menace was meh. Every character stopped to introduce themselves. The action was staged, detailed and derailed itself. We got full explanations for motivations and whilst it pretended to be in the middle of the story it really, really wasn't. Every character bio was played out on the screen, every prop looked new. With good editing an incredible film was hidden amongst the noise waiting to be discovered.
Turns out that A New Hope was much the same and it took a fantastic editor to chop, trim and reshape the mess into the classic. You will be cutting some of your best scenes, it is the nature of the beast, but do those scenes move the story on? Do they contribute to the building tension or slow it? Do they match the tone and style of the rest or do they jump out? If you had to submit a section with them in to an Agent with no other context, would you be happy?
I loved my prologue. I felt it set the scene. It had some wonderful purple prose but when I prepared a couple of submission packs and they asked for the first 15 pages I realised that the story had barely started due to the prologue. Taking them out and the handbrake wasn't just off, the novel actually had a rolling start with a lot of the action having already occurred.