Needs more detail in general, especially on the folds. Try and give it the actual image of overlapped scales instead of just separated sections of skin.
The filter is a bit obvious, could use just a tiny bit of blending. Otherwise, I like it, really gives a nice speckled fleshy look to the tail. For someone who doesnt know howto use filers, you did a decent job with it. Even if it is an amateur skin, its a good example of how using filters can be a good thing.
The claws, I would reccomend a complete redo. Try and do something with them, like scratches. Maybe a different color such as violet mixed with the grey.