I'm going the other way here. I didn't find the dark foreground all that objectionable. The reworked examples, though, made the foreground so distracting as to hurt the scene. I actually found the tree on the far right more interesting than the fence, at least in this composition, so perhaps cropping off the bottom 1/4th of the frame would create something even more powerful: stark tree against glowing sunset.
A word of caution, though, when working on sunsets. It's evident that many of those colors are going to be out of gamut for almost any printer, so you may be disappointed with resulting prints. Bright reds and deep blues can be real problem areas, so those need to be carefully watched.
Chuck