Glasya

I spent a couple minutes trying someone stuff and these edits may have improved (this section of) the image a tiny bit:

 
Although I am sort of worried the edits done would also harm the detail in the image.
 
This was edited in Gimp.
I used the 'Curves' panel to kind of bring the the different shades closer to each other, which got rid of most of the lines.
This was what I used, for reference:

Then afterwards only a hint of the lines was left.
The 'hints' were removed using the 'Hue-Saturation' panel in Gimp (probably present in other programs too, it's where you can edit the hue/saturation/lightness of colors separately).
In there, I was able to remove the last hint of the lines in the most obvious places.
 
Sadly though, the background does kind of get mangled by those edits, plus you are missing a lot of light/dark on the shirt too. But I think those might be the sort of editing panels you could mess around with.
Maybe you should 'cut up' the image digitally, so you can work on the background and such separately.

i joined with my two watercooled 1080ti's
 
lets get those points guys!

i joined with my two watercooled 1080ti's
 
lets get those points guys!

i joined with my two watercooled 1080ti's
 
lets get those points guys!

i joined with my two watercooled 1080ti's
 
lets get those points guys!

That's only a factor of convenience. 
 
Again, only a factor of convenience.
 
The way you phrase it this is wrong. The factors for field of view are distance to object and distance to background on one hand and the diameter of the entrance pupil on the other. Depending on the various definitions of the circle of confusion, neither focal length nor sensor diameter play a role in depth of field. That's physics. It is true though that in practice you get some lenses for certain FF systems that don't have a match on APS-C or even MFT. But they could be made. And then there's the question if you actually have a use for somethin like a 85mm f/1.2 FF lens shot wide open. I had it for years and I can tell you: you're not using it at f/1.2 because it has serious chromatic abberations and the DoF is so shallow that you either have the eye or the nose in focus. This is basically unusable. I basically never shot this lens on a faster aperture than f/2. Sharpness was phenomenal though at that aperture.
 
FF sensors can (!) have higher dynamic range and better ISO performance. That is if (!) resolution isn't pushed at the same time. Both ISO performance and dynamic range depends mostly on pixel size and therefore pixel density. If you compare an APS-C and a FF sensor witht he same pixel density and on the same technological level, there won't be any noticeable difference. Of course, if both sensors have the same resolution, the pixel density of the FF sensor will be lower and therefore the pixel bigger.