I don’t think you over did it at all. I love all the battle damage and wear, it makes the mask look like it’s been through a lot and has survived for centuries. I also love the rope or lace that you used for the stitching on the sides of the mouth. It works well along with all the other detail you put into it. I tired making a Jack of Blades mask of my own, I still have it but it’s no where near as good as yours. All I did was buy a cheap mask from a Halloween shop and paint it to look like Jack’s mask. It’s crude but matches to the original but I made a mistake and painted the part of it that were suppose to be purple around the left eye and under the chin red. If I had access to the same materials and tools you used I could probably make an actual Jack of Blade’s mask.
I suppose it's because with the remastered edition of Fable they're putting out, Jack's mask is completely clean. Oh well. The reference picture I used directly from the original game was pretty pixely as far as his mask goes, so I kind of had to guess what the details were. I think if you want really good results, then you have to invest a bit into whatever you're doing