I think your decisions on moderation are correct.
My biggest gripe is that spam posts are maybe downvoted quickly - and removed quickly enough - but they always make it to the RSS feed, which is - alas - my main way of getting new posts from Echo JS.
I've always proposed to allow posting news only when reaching a certain amount of karma points. I'd contribute with a PR, but it's also ironic that Echo *JS* uses a forum made with Ruby on Rails...
Ah yeah, the website is using Ruby / Sinatra actually, which is easier to start working with than Rails (which is great but relies on some code conventions).
But yes a bit ironic indeed :D
I've added some spam mitigation code to the repo back then, but it could still be improved for sure