There are a couple of places that could use a little more refinement, but don't be too hard on yourself. Most 18th carvers didn't turn out work as good as some today. They were doing it for a living and could not afford to lavish hours and hours to get the carving just right. If you will examine a lot photographs of old guns you will see that while there are a few true masters like Beck and Haines, most of the carving falls far short of perfection in design and/or execution. Sometime "good enough" really is good enough. That is not to say you should be satisfied with work that falls short, but if it is not quite perfect you are in good company (and historically correct).
Incidentally, I find it helpful to pencil in the design and let it "rest" for a little while, at least overnight. Invariably when I come back to it I find things that can be improved on.