All of these issues came right after 6.21 came along.
Before 6.21 my game literally ran perfect at a locked 60fps with no stutters.
I figured out what the issue is.
So for some reason after 6.21 vertical sync causes a lot of stuttering now. Normally I play on a 60hz monitor that I use for work and play.
I normally have Vsync set to on on my Nvidia control panel and I also have the frame rate to 60 on the game's settings. I turn off Vsync on my nvidia control panel and I set the frame rate to "none" on the game's option menu my frame rate is basically "free" to go as high as it can. It goes up to the 80's and 90's and hovers around there.
Basically now I have a lot of screen tearing (because vsync is off) but there is zero stuttering now. All the stutter that was introduced in patch 6.21 is completely gone if I turn off vsync.
The only problem now is that I have to choose my poison. Either turn vsync back on and get a bunch of random stutters or turn vsync off and have a stutter free experience but with screen tearing.
Also, the stutters are not real frame rate drops. Running MSI afterburner and RTSS while having vsync turned on clearly shows my fps as a solid 60fps with no drops when the game starts to stutter. Basically the game stutters but the FPS counter stayed at a locked 60 as the game is stuttering.
Essentially SE broke Vsync with the latest patch.
What I have been doing to alleviate this issue, is basically locking the fps to 60 with RTSS while having vsync turned to "Use 3D application setting" and settings the fps limit in game to "none". This basically locks my fps to a rock solid 60 and I have zero stuttering so my game is very smooth (just like it used to be with vsync before 6.21) the only problem again is that I get the occasional screen tear. But this is far better than having all these stutters. So I have been playing that way for the past two weeks now.
I hope they fix this issue in the next patch.