I like what you have with the added wrinkle on the other side. Although the shading of the strings......I feel like the avvies right string...the shading needs to be on the other side of the string. Since the light source is coming from the avvies right....it doesn't make sense the shading is to the left of the string....does that make sense? EDIT - I just noticed the shading of the strings are BOTH to the left of the string rather than the right...

As for the lightest shade - it's really only used as a highlight. In the case of your hoodie which I imagine is just a plain cotton hoodie...there really wouldn't be super high lights on it like there would be on satin or a shinier fabric. So you could be good just leaving it off if you want to. :)

Also - you could add a little more highlight to the outline on the avvies right if you wanted to. The outline is mostly shades 5 and 6...but you could use shade 4 if you wanted just where the light would hit it the most.