North South is a great attacking position. Back in the day, many grapplers felt it was a useless position. What really changed that thought process for the industry in my opinion was the North South choke. However, I rarely go for north south chokes, as I find other submission options more appealing that people sleep on.
The arm bar from north south is one of the strongest in my opinion, as you captured both arms, killing his defense and also not letting him know which arm is going to be attacked until the end.