Your stitching looks beautiful! Consistency is the key, and you get that by practice. If you are interested in smaller stitches, loosen the tension a tad so you can rock the fabric more. Fine, short needles can help also. But your sticthes look plenty small to me.
Glad there are more people who want to do hand quilting. Some quilts lend themselves to machine quilting, but IMHO the finest ones will still be hand quilted! :lol: