Regarding the 90th Perth skin its very good apart from the fact that the backpack has 51st on it still
Not on the texture, On the Specular and Normal maps, something I cannot help really, you will see that on many other skins too.
It's fine to implement your own, using OpenBrf. I'll give you a little Tut on it later if you want. (I didn't realize you actually skinned, i'd love to chat about it.)
Here's few more references, from when I was obsessed with making my own 90th skin.