Rebuilding BrickLink Tortuga with only my own bricks

After rebuilding the Alchemist's Shop using only parts from my own collection (you can see it on my profile), I decided to tackle Tortuga to go with the pirate minifigures I made at the LEGO Store. I had to modify a few sections because I was missing some pieces. So far I'm happy with the result, although I do regret using sand green on the tower. Dark bluish gray might have looked better, but I don't feel like rebuilding it all right now. My biggest disappointment so far is the water. I...