vertical monitor is a blessing and a curse at times. For just coding, it's great because I have more lines to reference at once. However when I show the directory tree for my projects my width is small and sometimes hard to deal with. Same problem with having a mini-map sadly.

I actually am right handed and read left-to-right. My dominant screen is my left screen and it used to be my editor screen, but I switched my code to the right because nowadays more of my work is server monitoring, communication, and review of code. The wider screen space is nice for this.