There are two main types of panels. TN and IPS. The TN panels are generally cheaper, have worse color accuracy, worse viewing angles but higher framerates than IPS panel. So you probably are looking for a mid to high end range IPS. I'm not up to date on current models so hopefully someone else will chime in.
If you haven't yet make sure your GPU is powerful enough to get a stable 60 FPS. My 1080ti works well for that but my 980 would often get 40 FPS in 4k gaming on demanding games.