32" 4k is nice as well, if you scale down to 2560x1440, or 3008x1692. On 32" 2x scaling (1920x1080 is just too big, and native (3840x2160) is just too small.
But if money is no problem, 3x 24" 4k, 2x 27" 5k, or 1x 32" 6k is really the endgame. That 2x scaling is just soooo crisp. :)
Significant difference. 32" 4k is not pleasant to read natively, and bringing it that close that is would be readable means you are putting things out of your focus and you need to start moving your head a lot.
Depending on how close we're talking about, it may not be so great, especially with a non-curved screen, because the actual angle at the edges is possibly not so great anymore. That's the case on my 32" LG, for example (with an IPS panel, FWIW).