I think you are being far too hard on yourself. This is a first attempt at a new skill and your art quilt looks good. will it get better as you add more ? Probably. Will your second or third art quilt look better than your first - of course!
Frankly, I think it looks amazing considering this is your first one. Definitely has some of the feel of the photo. So finish, and even if it doesn't meet your own standards of beauty - keep it . Then when you have done 2 or 3 more you can look back and admire how much you have improved.