The happiest I have ever been with my monitors was with 2x 24 inch 1440 displays (dell s2421sgf) - it’s not an IPS display but it’s a single panel high refresh rate with solid software support and good color mapping. I calibrated it and it was worse than my MacBook but only slightly.
Unfortunately they appear to have a shelf life of about 6 years and the panels are no longer made…
I also was looking for 24-inch 1440p's and was surprised they didn't exist. The closest is probably the 24-inch 1920x1200, which I do like for the 16:10 aspect ratio.
Does anybody else feel that 27-inch monitors are uncomfortably big? It feels less like something to look at work on and more like a movie screen right in front of your face. edit: I see xmodem expresses a similar feeling in a cousin comment.