Hey Stephen,
I saw this earlier but was driving, so I was glad that Ben told you about Waterfall Wednesday.
#3 is my favorite of the group. I like that window into those series of cascades and falls. A really sweet shot. I also like the extra photo you posted, the water looks great in that.
With your #4 shot, a nice perspective with how its framed with all those leaves. As mentioned about the shutter speed on that. Certainly going slower is probably the norm, but I did want to mention that waterfalls like that sometimes can be shot even faster, 1/400th or so and look really nice. When shooting that fast with a powerful waterfall that shoots out as much as that one, freezing the water is a good way to demonstrate the power of it. Now the shutter speed you did use, seems to be in the middle ground of not fast enough to freeze it, but not slow enough to get the water more silky stringy.
Jim