I just want to see 60fps, with decent graphics, at 1080p on a mid spec machine... I feel it won't happen though.
It won't, at least not with everything all the way up.
I would expect PS4 type graphics at 40-60fps graphics a 1080p on a medium-high spec PC depending on what you class as medium spec.
Then higher res and everything turned up (double AA, larger draw distance, higher res textures, more traffic) would probably still struggle to hit 60 at high-crazy spec PCs.
I would go in with those expectations then anything above that is a bonus

