I actually have 24" 1920x1200 main display plus old 22" BenQ 1680x1050 as secondary. I generally don’t like to have anything important open on my secondary screen, only stuff that I need to quickly reference. That’s why I currently have both the text editor and web browser side by side on my main monitor.
My plan is to get 1440 display, retire the old BenQ and put my current 24" vertically next to the new 1440 display. Though lately I’ve been thinking if I should get 30" 4K display, that would have enough space to put everything on one screen. Even with 4k display I still wouldn’t give up secondary screen .
One option would be to buy ultra wide display, but I don’t like those since while gaming I like to have discord and what not open on to the secondary monitor.