Judith,
A very nice series.
I finally had a few minutes to do a very quick edit of Dreary Day--not a polished job, but enough to show what I was getting at. I'll post it below. Here's what I did in photoshop:
1. I started by lightening the shadows with the image_adjustment_shadows/highlights tool. I also added a tiny bit of midtown contrast and increased color to bring out the green. I used a normal blend mode for this.
2. I slightly increased contrast for the whole image using a curve, with luminosity blend mode.
3. Finally, I selected the sky and used a levels adjustment and a curve to bring up contrast there. I used a normal blend mode.
Not a wonderful edit, but it shows ways of bringing out detail and increasing pop without losing the mood of the cloudy day.
As I wrote earlier, I find this kind of edit difficult, but perhaps this is good enough to be instructive.
Dan