I agree. Even though the sip crashed, perhaps you need to build up walls of your ship. Use different bricks with gaps in holes in the wall to look like punctured wood and where it is damaged. Also, I'm not sure if I saw some (haven't seen all the pictures) cannons. Make a cabin and wheel too. Even another deck!(You could take some plates and stick them onto the sides of the ship diagonally to look like splintered and cracked floors.)
I'm not the best at broken ships so that is the advice I give you. For the background/environment, make some big rocks that would actually look it could obliterate a vessel. Make it pointy and use slopes to make it look natural.