Wolfgang, when you said "practice plates", I envisioned hordes of right and left curls, some straight lines, maybe the beginning of a flower.
But you do really great work! I cannot keep the tip in the metal, resulting in skids and jerks all over the place.
Listen to Dave (Smart Dog, above) and Jerry WH. They are both recognized as really good engravers, and if they say you are good, you are.
But they are also right about the engraving matching the period that you are attempting to emulate.
Again, though, it is YOUR firearm that is getting decorated - so if you want, make it truly yours with your beautiful engraving. Ain't no flies on your work at all!