Honestly, lots of potential pit falls to this. For example, if differences go beyond resolution, say to frames rates and graphical effects too, that just doesn't seem like it'd be fair in competitive environments where such things can make more of a difference. Eg players having a gameplay advantage because of a hardware advantage.
Then with the whole VR thing. Right now the advantage of PSVR is its cheaper than the competition, both the headset and the system. If they sell a more powerful but expensive console, just to play the same not that amazing looking games as the PS4, but in 4K at a more expensive cost, surely in terms of consumer mindset it'll start diminishing the price difference between PS4 VR packages and PC VR packages, like Oculus for example? I mean, PS4K VR games are still going to have to run on the PS4, so it's not like they'll be super state of the art. If it's that much more expensive, it may almost start making Oculus or Vive plus a half decent PC rig, sound more viable.