Nice photos. I am not sure but I assume the reviewer wants more depth of focus. They are a little blurry around the edges.
…017: Chromatic aberration at the highlights. My personal note: The horses eye could be more appealing: sharpen, lighten up, add contrast.
…premium: the picture is missing overall sharpness. Especially, the eye and the surroundings should be sharp. The eye shows also strange colours. That may be natural, I'm not the expert here. The noise level in the picture is quite high, so I suppose that the sharpness loss is also due to noise reduction.
…697: Looks near to perfect for me. The picture could get a hint of sharpness and a hint of local texture, but nothing dramatic. You could try with minor adjustments and then resubmit.
…4zu3: That was a hard one. You have chromatic aberration in the eye reflection.
I would also add sharpening to the overall picture and make the eye a hint darker.
very nice pictures love it