Micah,
You've done a very nice job with this rifle, and it "shows" well. Please don't feel intimidated by the work of others here at ALR, we're all enthusiasts, students of the Longrifle, and all started somewhere...
I think the architecture looks good and the overall craftsmanship is excellent. That's important, and the "base" of a nice piece.
My two suggestions deal with the "bells and whistles", the carving and engraving. With the engraving, you might want to try some shading or adding lines inside the larger leaves, similar to what you did with the flower in the finial, to add some depth.
Take a look at some of your favorite builders works and look closely at the wood carving. You'll notice the scrolls flow in the design, and have proper proportion. If you look at the bottom right C scroll of your rifle, you'll notice the top is a little off the "flow". I think the "shank" of the top portion is a little flat and throws off the C scroll. If that makes any sense at all...
You're well on your way to great things. The "bells and whistles" just take practice, you've got the hard (and important) stuff down. I think you've done really well with the lock and side plate panels as well, and the finish is very well done. Thanks for posting the photos and we look forward to seeing more good work in the future!
Ed