Hi Chris,
Is it worth joining if we don't have expertise on the technical side just to add numbers? Or is this really only useful if one has that expertise?
I think it's worth it, but take a look at the
example questions on the site to get a better idea. They're not all nitty-gritty technical. As long as you understand the concept, you can answer the questions of those who don't. You can also contribute by asking questions, if there are aspects of bitcoin that you'd like to understand better.