The one thing I'd like to suggest is that instead of the thick black outline on the hills, maybe consider just anti-aliasing them to the background? The outline sorta messes with depth perception and makes it seem kinda like they're just as close to you as the castle.
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The one thing I'd like to suggest is that instead of the thick black outline on the hills, maybe consider just anti-aliasing them to the background? The outline sorta messes with depth perception and makes it seem kinda like they're just as close to you as the castle.