Personally I would add a lot more triangles on the sails to give them shape and allow them to bellow.
Likewise the cabin is somewhat minimal, and the various poles (mast etc) look out of proportion chunky and are usually tapered.
Also without seeing a wires it's hard to tell how many quads you've used on the hull but it looks proportionally high by comparison to the rest of the mesh. And you might want to look at smoothing groups to have some sharper edges around the top of it.