1st, I'd say is just a little too bright at the top, I mean I'm all for punchy high contrast or high key or whatever, but I just think it should probably be a bit darker, also I think you've shown a bit too much of the space below the boat; again I understand you've probably tried to go for an edgy composition, but I think it would work better with a larger breathing space for the back of the boat.
2nd, Everything is perfect - beautiful soft lighting, great depth of field and background, except I'd like to see all of both feet; it's just ever so slightly chopped off.
3rd and 4th, Colour for sure on this one, and well it's very nice apart from the left side is chopped off. I think I would have done two shots merged to show just enough of the whole walkway.
5th, great colours, nice composition using the reflections, I just think the railing is a bit off putting.
6th - does nothing for me sorry!
If you wouldn't mind critiquing my 'Morrocan street photography' in return please?