I agree with Pat. If you're satisfied, that's all that counts. Like most of us, we're looking for guidance before we jump into the deep end, especially with an engine that costs over a thousand dollars! Maybe even more than that, acceptance or a pat on the back.
As I mentioned previously, weathering is subjective & everyone has there own opinion. Not all of us wants a weathered engine, but if your layout has distressed or weathered buildings, vehicles or scenery, than some wear & tear on the engines & rolling stock is natural. One thing about trains, no two subjects should ever look exactly the same, if that is even possible when weathering.
Nature is the best teacher & many of us are trying to duplicate that on our layouts, unless of course you favor the classic toy train approach. Because it's your layout, if you are satisfied, that's the main thing like Pat said.
When I was 16 years old I weathered some HO Bachman & Life Like inexpensive rolling stock. I studied some articles on weathering models before I got started. I used my airbrush & was very happy with the finished result. I anxiously took them to my local hobby store & the comment from the shop owner was, these look like a talcum powder factory blew up all over them! I was devastated & never forgot. Until that moment, I thought they looked great running on my railroad. So much better than the out of the box, freshly painted versions. I study photos & nature more carefully now.