First of all I just want to say well done, it is a great capture and the picture is very successful. However there is something's that I feel could be improved, or there would be no point doing a critique.
The sky in top half of the photo is fantastic, great use of colours to give a very deep feel to the image. The slight transition of blues from dark in the top right down to very pale in the bottom left really make the image stand out, even as a thumbnail.
The land that is visible in the image is fantastic, I love the haze that creates a mystical feel to the image.
However I do not feel that the reflection in the water is very successful. Mainly because it is not very clear, im not 100% what it is im even talking about, but something I do not think is right. It is slightly blurred and the water surface is not visible.
Despite this it is a very well balanced image and you should be very pleased.