Photographed the Lower Falls the other day from Artists Point and wanted to get the rainbow in the mist which you only get in the morning. Rainbow lasted about 20 minutes.
I like it a lot too. Composition works well with the river exiting at the lower left and the falls starting close to the top. My eye starts at either end and flows through the image. I tried a Local Contrast Enhancement using USM on a BG copy at 30/60/0 reduced the opacity to around 50% and then added a curves adjustment using a mild reverse s-curve. I liked the affect on the falls and trees & rocks details due to the LCE and the reverse s-curve evened out the tones to the whole image.