Here's my try:
1. Make a duplicate layer.
2. On the dupe, run G'MIC Colors-Zone System: raise the shadows zone to 5.
3. Mask this lightened layer to affect only the dark area at the bottom of the image (I tried a luminosity mask but didn't like the result -- next I tried Colors-Threshold on a dupe of the original layer and this worked pretty well. I used a soft brush to refine the mask edges. I brushed out most of the trees because the Zone effect just didn't look natural there.)
4. New layer from visible, apply Curves to make a slight S-curve for contrast. The Zone System filter in Step #2 often needs this adjustment or else the image has no BLACK pixels and looks unnatural. We need
some black, just not as much as we started with.
5. G'MIC Repair - Ian's Noise Reduction.
6. Highpass sharpen.
I left the colors alone, although you could certainly adjust them. Arguably, this is a better photo if you leave the foreground in silhouette and all the attention on the sky. But it's a good opportunity for us to share ways to brighten shadows, even if ultimately we decide not to ;-)

Hmm... I should have masked out those chimneys and toned down the roof.
P.S. It makes me sad to hear GC users say they can't handle a file this size. This is the file size you get from today's cameras. If GIMP doesn't work on on a 4200x3200 pixel image, then GIMP is no good for photographers. I happen to know that's not the case, thank goodness! Unless you're trying to run Dream Smoothing...
And now I see that GC won't let me upload the full-sized file. I understand that server space is not infinite. But anyone who is serious about photography will not be able to compare editing methods by looking at a severely downsized image. Do we have a good workaround for posting large images?