Is your style appropriate for what you’re trying to produce? For example light, easy sentences might not be apt for a dark piece where I’d expect the words to be heavier, darker, to conjure up the right mood. Wodehouse stuck to what he knew - humorous prose - for a good reason. And his light style is perfect for it. Likewise horror writers write in a very different style appropriate for their work. So make sure your style matches.
Are you getting into the heads of your characters well enough? If someone asked you an unexpected question about any of them, could you, based on your knowledge of them, answer it?
Is there enough going on in your story? Do your characters change? Do you show how and why? That is the story after all!
How well do your characters adjust to circumstances and/or other characters as they change? How your characters react to and handle changes reveals a great deal about them.