A cover and a title can curse your amazing book or it can elevate a mediocre one. When someone buys your book they are drawn in by the cover and the title. If it's not applicable to the genre or isn't flashy, you're gonna miss an opportunity to draw people on. The cover & title sell books. They don't know-how good your book is until they've read I but they know whether or not they are drawn in by the visual
Don't fear the editing process. Your babies are still protected they are still yours, and you did a wonderful job making them. Edit yourself, and let an editor look at it. It will only make you and the project better
Write bin chunks. I write on scenes. So when the scene ends, I stop and process. If it's been an emotional scene then I let that emotion breathe before I go back in there