Thanks for your points, Lazer_one.
1. I agree with the staircases.
2. As there is no waterline on the actual ship, it was left off the drawing. If the SB rule is to have a black line to show the waterline, then it will be added. IIRC, there was a discussion recently (In Japanese WWII ships thread) which established that it wasn't always necessary.
My positioning of the bow thruster comes from this picture:
I agree that the bow can be better shaded. Underwater hulls are not my forte!