Hi Tom.
I'm certainly no expert but i'll give you a couple of pieces of feedback.
Firstly, the horizon needs straightening. Secondly, i'm not sure what the focal point of the image exactly or what your are trying to give the viewer? Thirdly, i'm not entirely sure but the cloud looks to have some blown elements, ie no detail, just pure white.
Other than that, good colours, not a terrible exposure, certainly better than my first attempts!