#1 Does nothing for me. I know the reasoning behind it, I have taken many location markers in my time. But it is not a photo I would post for critique. Also, these days I Geotag my photos instead. I carry an external-to-the-camera GPS, then match photos to track log using the time stamp. If you are after more detail, look in "Equipment reviews" on this site for more info.
#2also seems to be a nothing shot to me. It just doesn't hold my interest at all
#3 is great. Perhaps move the focus up or down a little the get the waterfall further from centre.
#4 just misses the mark for me. I would like the plant moved so it is at the junction of the slab perhaps. Just speak sternly to the gardeners OK
Another possibility would be to step back a couple of paces and just get both corners of the slab the chair is on, then crop top and bottom to bring the vertical framing back to what you have here. The result will be a pano style shot with, I think, stronger visual impact as you will no longer have those diagonals leading out of the frame.
Remember, you can always crop stuff out. It can be very difficult to put in something you have missed.