I appreciate the concerns and I will give them a lot of thought.
Trolls are a common issue across the web, we are not unique. If anything, we receive huge praise for having relatively few trolls here compared with most other forums. Our current system gets a lot of praise and has achieved fairly amazing results. There is always room for tweaking, of course.
In my experience, the best path is to always treat newcomers with respect and to gently guide them by modeling healthy behavior. Many people come into a forum with an "expectation of behavior" that is shaped by other wilder forums. It takes them a little time to realize we are different. We need to give them that time, and show them by our actions what we expect, so that they can learn how we are here.
I run two other forums and this same sequence happens. "Wild posting teens" come on, they are treated kindly, they realize that the forum is different than other ones they've been on, and often they adjust and become amazing forum participants. It's like running a boys & girls club and bringing in street teens, and watching them develop into amazing young adults. It's very rewarding.
As I said, I will continue to ponder this. For example, I don't feel the solution is to jump on and ban individuals in this category. I favor the carrot approach, not the stick.