Thanks for the evaluation. For me, I often get so involved in a particular aspect of a posting that I overlook the overall result. Could you be a bit more specific (maybe in just one of the images) as to the jpg artifacts that you are seeing. It would help me key into it next time.
I used LR4 for my post processing. I've redone these images at a smaller size as I certainly don't want to misrepresent the camera. The vertical size is now 768 pixels. I tried reducing the sharpening for screen to "standard", it was set at "high" but the results looked "mushy" sharpening is now back to "high".
I did reduce the luminosity in the foreground of #1 and #2.