The GDPR Exists, data protection laws exist, and it is your duty to inform other of what you are doing with that info, not the users. Premade docker images are shit for security, they are almost every time based on an old Version and such are vulnerable to Hacks like the SQL CVE just some Weeks ago. Your data will get leaked, your users data will get leaked, and you will be liable to all damage. If you want an alternative to the usual petition sites, you will also need to implement a working bot protection, trolls, etc, of which cloudflare or other CDNs will only do a fraction of. Your homelab needs to have a good uptime, regular sec updates, and competent security. Your own network will get ddosed as a result of the traffic, if you don’t have a good network plan. All of those are just a few things you have to think about when publishing to the internet, and which you apparently just don’t have the knowledge to do.