Hi fairground. Nice venture into "not fully automatic" land. But you have to tell us what you did manually?
As to the pics:
I think #1 is too cluttered above the water and one is not sure whether you wanted to (a) concentrate on the gushing water and winding river or (b) on the uprooted tree lying across the river.
Perhaps a lower point-of-view could hsow the river less cluttered so could be better for (a) and a little more zooming in could have isolated and focussed more on the uprooted tree if you had (b) in mind.
#2 is good, just crop off the left side and try to get/add a little more contrast in the sky to make it even more dramatic. I think with the underexposure you achieved there's enough detail in the sky to be worked upon.
#3 is one of my fav themes. And it's quite a challenge. I think you have picked up a nice frame, exposed correctly, but i'm not sure whether the dof is great enough to captured the twigs of the far away trees sharp enough. It might
also help to increase contrast or even convert to b&w like what I did in this picture:
This concentrates on the underlying geometric structure of the image...
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