You're editing skills look a lot better than you give yourself credit for!
I like what you've done with the post-processing!
A good rule of thumb for cropping is the rule of thirds. In other words if the sky looks good you could leave a little more for the photo to breathe, something like 2/3 van and 1/3 sky is still good (just avoid 50-50), kind of like avoiding putting the horizon on a sunset in the exact middle of the frame.
Rich