Some dramatic moving waterfall details here, some of which will need to be carefully rendered in print. Just enough size to make sure more individual streaks of water are visible through the more general motion blur, just barely enough shadow detail to render the rock behind visible as a sharpness anchor.
I also feel like this image owe a bit to the stylistic influence of John Paul Caponigro, who is worth your attention. (He does, intentionally, do a lot of what us purists might call manipulation, but there's no subterfuge here, just some really wonderful art.)
This is Seljalandsfoss in Iceland. While I have at least a dozen waterfalls that I truly love, this one and one other (Skógafoss) really seem to lend themselves to experimental photography, capturing shapes and forms so chaotically changing and transitory that one never quite knows what one is going to get, and repeatedly shooting the "same subject" dozens of times may, with patience, lead to surprises and the occasional extraordinary result. In this case, the mirrored light and dark flows of water were not even hinted at in any other frame.
While a great deal of my photography is composed in a very controlled form, this opposite strategy is something I enjoy a lot, and that has often produced good results for me. Find an appropriate subject, and give it a try!