I keep going back and forth on multiple monitors. I'm using one big one right now, which felt better than my previous setup of two displays at first, but now I'm thinking I might want another smaller one off to the side to monitor running terminal output ... ugh.

I will say that two monitors has the significant drawback that there isn't a single central display, so you're always either tilted to the left or to the right relative to your desk. That's not good ergonomics.