Since you asked for a critique:
I agree that the box lid is a bit too angular and would look better with a less abrupt curve, and in addition the carving is off-center and the design is not particularly attractive to my eye. Remember that the box lid currently on the Faber rifle is a modern replacement - the shape probably follows the flat on the butt and is therefore probably the same as the original, but the carving is a modern guess that Shumway thinks is probably too ornate - ergo, no need to copy it. I suggest that you consider replacing it - it doesn’t look up to the same standards as the rest of the gun, and unfortunately is something of a focal point for that side of the stock.
The cheekpiece is a bit long, but I think it also tilts up too at the front and would look better if it was at the same angle as the lower line of the butt, or, even better, was tilted slightly down at the front as the original was.
To be really nitpicky, the edge of the sideplate panel right above the front lockbolt would look better if it came back just a hair further, and I think that the top edge behind the barrel could come down a bit, but that might just be the camera angle.
I am not too thrilled with the trigger guard, since the finals are octagonal and don't match the rest of the furniture, but that may be just a matter of personal taste. I concur that it would benefit from filing down the finals a bit.
The tang carving is a little short and wide for my taste, and the lines running along the barrel tang don't flow very well. Likewise, the carving around the nose of the comb could use a little more sweep in its curves, if that makes sense.
Having said all that, I think it is a very nice gun- the overall proportions are pleasing, which is very important, I think, and in general (apart from the cheekpiece) the lines are nice. Inletting is nice and tight, which must have been difficult with the side plate and butt plate! I also see that it has been engraved, though the pictures don’t show much of it, I am afraid.
BTW, welcome to ALR! You might want to fill out your profile a bit, as a lot of folks here like to know something about who they are talking to and might be more forthcoming if you do.