The SMTP protocol is not going anywhere. Deal with it. It's really straightforward to fix your griefs with e-mail: Write a MUA. If it provides good value over

The SMTP protocol is not going anywhere. Deal with it. It's really straightforward to fix your griefs with e-mail: Write a MUA. If it provides good value over normal e-mail clients and handles normal e-mail well then it will quickly become popular. If it's not backwards compatible then it's just yet another "todo-app" and will very likely not take off. tldr; There is no such thing as "replace e-mail".