We have maybe around 10 spammers a day, maybe a little more (we’re three people moderating and I know they also delete several accounts a day).
Discourse, Akismet, and user reports work like a charm, we need neither automation nor nuclear option. 
Suspected spammers don’t take much work and are fairly rare, but I wonder if there are techniques or third-party services that can help identify manually a suspected account.
Though I add that this is not a real issue to fix on our forum, I’m just wondering.