Hi Peter,
my 2-monitor-setup started with 2x Eizo L767 (4:3, 1280x1024). As I got to print seriously, I replaced one with a Quato 262ex (16:10, 1920 x1200), whose ratio and pixel size I really liked. When it went wrong unexpectedly, I was considering a big 4k screen, something like 32" … but limited with size & price (I was just going to finally get a new, fast machine) I decided for an Eizo CG 2730 (16:9, 2560x1440). I set CG 2730 to 125 % and L767 to 100 % (WIN 10, NVidia GTX1060 6GB).
BTW, my viewing distance is about an arm length and for editing I’m using an extra pair of glasses (single vision), while at work I was fine with varifocal glass. – When editing in PS etc, I have most of the palettes on the extended screen, while in PL4 it looks like this 
… left …
… right …
have fun, Wolfgang