I think as a long time vb admin there is a point where you want a community to remain active but technology has passed their software by. Change or get swallowed up. We're a local group so there will always be a need to exist so advancement of the user experience is crucial.
Let me know if you need a vb install to poke around in. You have my contact info in profile and I'd be happy to chat offline to see if we can help the process along and give NodeBB another way to pull in users (self or service hosted) from the vb group.