This is being considered. The current intention is to add a superadmin role, making the default admin account just a member of that role.
This will allow you to create new superadmin accounts, capable of logging into the shell, adding ssh keys, and any other features limited currently to the named admin account.
Second, you will be able to disable or demote the named admin account.Cameron Slade commented
I agree whole heartedly. On every device we manage, we always change default the admin account name. This is a must have.