I think your quilt is beautiful. You certainly can't tell by looking at it that it's your 4th piece.
I read all the replies and some of them suggest manners of quilting that may be beyond you at the moment. If I read your original post correctly, you have not handquilted before. I spray baste, then pin over it, with no problems at all. No drag on the needle ever. I still pin here and there because I'm paranoid that the spray will magically stop working.
For quilting motif, since it's your first attempt at hand quilting, I suggest you do a basic outline either in the ditch or close to the ditch around the blocks themselves. Then, I would quilt around the center square patch or the pinwheel in each block. When you turn your quilt backwards, it will look like a little square surrounded by a bigger square.
Vines, feathers, hearts and other freehand things can be difficult if you don't have a lot of experience.
Start in the middle of your quilt. You will notice your stitching improving as you work on your quilt. The size of your stitches aren't nearly as important as the consistency of them. If your stitches are a bit big, shoot for all of them being a bit big. As you quilt, your stitches will naturally get smaller.