I also had a similar experience with hand quilting my second quilt and didn't like what I had done. I later realised that I had a batting that was too thick and there was no way I was ever going to get smaller stitches. So I think the flannel backing is not helping your quest. Having said that I like what you have achieved and like me you can't expect yoruself to get everything right perfectly on the first try. I love how each experience of quilting teaches me something along the way. Every time I do a quilt I find there is something else I could do better or differently. I have made a small doll quilt to practice some hand quilting and feel better about what I have achieved but once again ditched it for a year thinking I was making a hash of it. Be kind to yourself and let yourself grow through these experiences. You will make a great teacher for others having been through all the trials. Keep up the great work.