PC Master Race

I currently use my laptop next to a monitor with 21" but I am thinking about an upgrade. I casually play some light games, nothing competitive. The rest is a lot of reading, office or coding work and some multimedia.

What is a nice setup in your opinion? One big screen with 27" or two smaller ones with 22" or 24" each?

I did some research and found for a 24" screen 1080p and for a 27" screen 1440p as a minimum. So I figured a 24" 1440p screen would look awesome. Do I miss something about this finding? Is 2K too much for 24" to even notice it?

The problem I have is my desk is only 65cm wide and I frequently have a book or a piece of paper between me and the keyboard+monitor. The monitor uses 22cm and the keyboard another 14cm so there is just enough space for a piece of paper. Many of the modern monitors have huge standing feets and there are not always good measurements given.

I also thought about a monitor arm but I don't know if that would help with my small desk or just create more hassle after all.