@delta the last step can be challenging. You need to be close and have working camera (yes, people have broken cameras) to scan QR, or have an already established communication channel to send the link, which in slme situations defeats the purpose.
There should be some human readable / easy to memorize or pronounce "nickname", "username", "ID" or something, so than you can tell someone "just type John Doe once you install DeltaChat to find me".