sunset over the fence

The colors are brilliant, and I don't think it's dark at all. The black fram just kills it for me since it becomes part of the silhouette of the horizon on the bottom. The idea of a frame tells the viewer to look past it into the photograph itself, so when the shapes of the silhouette form with the frame I look past them. It's such a minimalist composition, so every part of the image is important, with the deck/fence adding depth in the foreground that you can look past and appreciate the limitlessness of the sky. If you must put a frame on it, I'd suggest switching to white, which in turn would trick the eye into believing the entire composition is lighter which could help with the darkness conundrum.