Thanks for taking the time to check it out, I will look into what I can do to improve those issues. It’s basically impossible to get usability insights like this when you’re the only person working on something, so this is much appreciated, thank you!
Like promotional emails? Not at all.
I’ve added features that allow admins to prevent their instances being used for spam. These are explained in the abuse mitigation section of the docs.
Rate limits can be set for authentication emails to minimise spam. The only other type of emails sent to users are reply notifications (when someone else replies to their comments). This is enabled for each user by default (if admin has enabled this feature on a per-location basis and globally), and can be disabled by users on the main panel.