Thanks for sharing these 2 images and welcome on LL!
Those are gorgious skies, but the image do, in my opinion, suffer a little bit from the lack of foreground and subject on the lower part of the image.
You might try to shoot a bit earlier so as to have some more light available to lighten up the foreground, locate yourself near a foregound that is able to reflect some of the sky (water for instance) or take a different approach and focus only on the sky?
Thanks for the feedback. Yea, I do need some sort of foreground. I didn't want to angle the camera down in those shots because the frame would include roofs (I was shooting from my back porch). We have been having some great skies lately. I'm going to try and hike up a nearbye mountain around sunset/dusk and capture a more unimpeded view of the sky, mountians, and water. And of course, some sort of foreground object like a tree, rock, or person.