Thanks! I had a feeling the vignetting would be the first thing to get mentioned. I kinda like it but thought it might draw the same feeling selective color draws. I edited my first post to include another without the vignette and a bit more contrast, but I think the silver sky in the first looks better.
The lighter sky in the first image is good, but perhaps this could be realised with a curves adjustment lightening the sky tones rather than the vignette. Otherwise, a very good photograph.