I'm partial to the off topic boards (like this one!) since I don't currently have a site of my own, so it's the easiest for me to post in and get involved with since it's easier for me to relate to the topics being shared. Not that I can't relate to site ownership topics, but I largely speak from past experiences. I'm also partial to the Social Promotion Services board for... reasons. 👀
I also enjoy answering questions in The Hot Seat! Always fun doing that!