Thank you for the information, Sailingdog. I designed the pilothouse without considering the possibility of leading lines aft. Other than that, its a good design with space for a nav station, galley and engine room with headroom and good vision from inside and from the cockpit.
I have a place I could mount a winch inside, but I'm reluctant to create an opening for the lines. There is room to grind on the pilothouse roof just inside the companionway (on top of the engine room), but as you said the system would have lots of friction.
The other possiblity is to lead all of the lines aft to the cockpit by placing turning blocks on (reinforced) stanchions close to side deck, and perhaps using a Murray winch on the side of the cockpit coaming.