I'm adding my $.02 as well. You are building up dollars on this one!
I hand quilt all my special projects. I took a mini class on it once, well it was more like watching a demo, and I just couldn't get it. When I moved down south and learned quilting bees are alive and well, that was when I learned. Most of the points I use when I teach has been covered here.
Size is not nearly as important as consistancy. Yours all look similar in size and for your first project, that is excellent.
It looked like you originally posted you knit as well. Certainly, your first knitting project didn't come out perfect. It takes time, like anything else, to find your groove.
I started a thread with questions about handquilting on flannel before I did my last queen size quilt. Everyone talked about the importance of washing it and that it wouldn't be hard to quilt on at all. Well, I washed the daylights out of it and it shouldn't shrink much more. I found it incredibly difficult to quilt through the flannel and I don't think I'll put flannel on another one to hand quilt.
Whether you stab stitch or rock your needle, it's your method that's more important than anything else. Over time, if you keep your consistancy even, your stitches will get smaller.
I recently saw a program on F&P about utility quilting and using pearl cotton instead of thread and making big stitches on purpose. Honestly, try as I may, I cannot get my stitches that big. These last 5 years of hand quilting my stitches have gotten small and I can't get them big again!
I hope some of this helps. You are welcome to PM me anytime and I can try to be of assistance.