Good call on locking your framerate. I just trust the VRR to do it's job, but not sure how much it effects my aim.. it doesn't seem to be a handicap thus far.
Performance wise I have no idea what's going on with this engine.. its definitely different from anything else I've dealt with. I think there is a lot to come in terms of optimization on PC. One thing I am noticing, same with forza I guess, is that the difference in quality between low and high is rather negligible.
the game also doesn't like Gsync is what I found, the game feels definitely smoother after locking tge framerate to half refresh for me.
I think Digital Foundry noticed something similar on Series X during their Campaign preview video they did. I think they said the game felt stuttery even on a VRR TV, and I kinda feel the same when using Gsync...
I kinda feel the engine doesn't like fluctuating frametimes.
it could be a similar issue Prey on PC has, that game does not like variable framerates whatsoever. camera movement and character movement will SLIIIIGHTLY differ depending on framerate I found. so when I played that on my old PC, which could not hold a steady 144fps (refresh of my monitor) of course (that GTX1070 was good but not that good), I noticed that as soon as I move and the framerate fluctuates everything felt stuttery even tho I have Gsync...
so I locked the framerate and it was absolutely smooth from there on out.
I feelt similar issues with Infinite but not quite as bad as in Prey, more subtle... it feels more like a slight frame stutter from time to time to me, where prey felt like it had constant hard framedrops.