*I really like my Asus monitor, it's better than my Dell that pleased me in the past. LG apparently makes good monitors too, but more for graphic design professionals and aren't the first thing to mind for gaming monitors.
*I think G-Sync (and Free-Sync, but I have an NVIDIA card) is more important than refresh rate. My 120 hz iPad Pro screen is really nice at high FPS, but a sync feature is more significant/noticeable once you get past 60 fps
*I have monitor mounts, so huge screens (and curved screens to make up for having a huge screen close to your face) are less important to me. 24-27" diagonal are fine.
*The main things I look for in gaming monitors are no input lag (no or minimal processing, unlike a TV which all are slow), multiple inputs (I have a Mac, PC, and PS4), and low ghosting.