It's better to cater to the most hardcore fans of the topic.
Some people worry about this. They worry that if the discussions are too technical, too geeky, too wierd, too extreme, they will lose the less committed.
This is rarely the case.
It's the most committed fans of the topic that attract the less committed. By encouraging and facilitating the geekiest, hardcore, technical and weirdest discussions, you get the people you want.
Your audience see the geeky discussions as a signifier. This is the community for them. This is a place that accepts and embraces their wonderful wierdness. This is the place where they can be themselves and talk about the topics they can't talk about anywehre else. It helps develop a stronger sense of community.
You shouldn't worry about the discussions being too technical. You should worry that they're not technical enough.