I really love #1, and see nothing to really critique. GREAT shot.
#2 would look a lot better with a longer exposer to smooth out the water.
#3 is just boring and crooked, sorry.
On #4, again a longer exposure would add movement to the water and clouds, and with some more DOF (foreground is OOF), it would be a great image. Nice composition. Same with #5, you may want to invest in some ND filters. You can pick up a 2-8 stop variable ND filter for $150, and it's one of the greatest investments I've made in photography.
#6 is alright, some fill flash would have been nice. It's just not an eye-catching scene though.