>>3420425>>3420451From where I'm standing it looks more like a severely underexposed image. Yes, camera with higher ISO performance would surely help but it's not fixing the basic issue with the weird exposure.
If it would be better exposed we wouldn't need to push it so in post and the highish ISO wouldn't be so noticeable.
f/125 and f/4? Lower that shutter speed, one stop slower shouldn't be a problem and open that aperture more. If not possible, invest in a better lens before you invest in a better camera. Get a "fast" prime, or atleast something around f/2.