That's my order too. Out of curiosity where would you have cropped no.3? It works for me as it is, but would be really interested to hear a different perspective on it.
I'd have cropped roughly the bottom third away. There's a rock on the right hand side that looks a little like a face in profile. I would crop at the point where it changes direction from curving out to curving in.
The main interest in the scene for me lies in the water and the illuminated rocks, and this crop concentrates the attention on this part of the frame. I'll be honest: I find it hard to judge with such a prominent copyright banner that catches and holds my attention far more than anything else in the scene. Hiding it does give a slightly different perspective on the image and shows a scene where the centre becomes the water and the waterfall. In this case, the water assumes a flask shape with a rounded bottom and a thinner neck (formed by the white water). The overall impression is then one of calm (despite the rushing water), and the main subject is the stream.
My suggested crop converts the image into a panoramic format, and shifts the attention to the surroundings which then become the main subject, with the attention concentrated on the fern (?).
Both the original and my version appeal to me, although in different ways and having essentially different subjects and moods. If the original stands uncropped, I have to say that the light edge to the lowest rock on the right hand side destroys the symmetry of darkness at the bottom of the frame on the left, so I'd burn it in a little.
But I should emphasise that my crop doesn't so much improve an existing image as create a different one which I prefer; and personal preferences were the order of the day in this thread
Just for semi-completeness, I've added brief comments on the first two as well.
No.2 works well for me in terms of the angle and framing, but the contrast between the very dark foreground and very bright foreground is too much for me . . . just not sure where my eyes should be focusing.
In my case, it's the angle and framing in number two that are the problem. It's an pre-eminently natural scene but photographed in an unnatural manner. The upper half of the frame invites you to look into the distance; you're looking across the scene and on the hills beyond. Well, the banks, anyway.
Now look at the foreground. The flat rocks are seen as though from above. It's the effect you'd get if you used a fisheye lens and produced a landscape with your own feet in the foreground, seen from above. It isn't the way I look, and I find it disturbing. That can be a good thing if the intention is to disturb, but on the whole it seems more likely that this should be a scene of calm.
The effect of the rocks is intensified by the sloping tree and rock on the left. The overall effect is that of a whirlpool, swirling round and round and dragging everything in to it.
So that's two points for a disturbing, slightly menacing scene; and that seems at odds with what appears to be the intent in the other two images.
Number one - well, I can agree about the black and white rendering, but my biggest problem with this one is the foreground interest. The rocks are positioned to be prominent, but lack the texture and inherent interest to sustain them in this role. The large light triangular rock bottom centre calls attention to itself by reason of its lighter colour, and then works as a pointer to a square rock which is out of place in a scene where triangles are more common. There are a few other points in this one that I would pick up on if I were attempting a full critique, but as I said in my first post that wasn't the objective of the thread.