This looks really cool, but I'd prefer a personal tier option that I can host myself - this is auth after all.
...and that's OK. You can offer self-hosted for the paranoid (or those who are not paranoid but merely reasonable and wish to engage in straightforward and legal activity like communicating with government whistle blowers), and offer the hosted version for those who value the ease of use. As a consumer, the fact that you offer both would increase my confidence in the hosted version.