I love the colors and tones James. But...
Landscape format would be better suited for this photo than portrait. You have the horizon almost dead center, but there is not a lot going on in the sky.

Suggestion- Shoot Landscape, lay on the ground, get more of the foreground in the photo, that is where the interest is. The interest in the clouds ends with the pink, so there is not really any reason to have all that blue empty space.

Just a suggestion. I do love the colors!