A monitor doesn't change you'r fps 😉. The biggest feature I find is g-sync, which prevents screen tearing.
People say 144hz is waaay better than 60hz, but it isn't really (I got one btw). You would only notice the difference when going back to 60hz from 144hz. Ips panels anyway are really noticable. Ever noticed sitting watching tv far to the left or righ? You will notice the screen is different, the colors are darker, generally it is harder to see what's going on. An ips panel makes the screen look good from whatever angle, and it has great colors.
I say find a 1080p or whatever you'r resolution is with a ips panel, 60hz. Twi screens perhaps (just make sure to get small bezels = thin sides).
Imagine 2 of this screen, check out a...