@ U-HAI, some questions.
Do you have a link in which I can see what you mean exactly when you describe the painting? I know it was lower-black and upper grey-blue-ish, but I do not understand what you mean by "and then whent to black , like the lower".
For the propeller I used my Revell plastic model kit as inspiration and that is why I have put a 3-bladed prop (Revell

). Will read more and put the right prop.
The anchors for ropes I have made visible because I think they look cool :P
They can be removed without any trouble. In fact I did the same about the Ohio class (which also retracts many gizmos inside, but I left them outside).
Edit: this is my first Skipjack ever so what you saw was not mine. Do you remember where it was mentioned?
Edit2: I have this model (ok this belongs to another guy, but I have an identical one)
http://www.modelshipgallery.com/gall.../ph-index.html