I recommend this; and it is what I do myself.
The problem with password removal is not security, but system. It is a process and when that process gets removed, the system gets balky.
This is why even Autologin causes issues.
But using a 4 digit PIN is quick to enter and easy to use while keeping that process in place.
One issue may be that when you change your password, the PAM authorization is set to require a lengthy password, even if it is not set at point of install. We can change that.
To change the password length requirement, please see this post:
To change your password, in terminal run:
passwd
Then enter the current password. Next, following the prompt, enter the new password (4 digit PIN).
As an aside, I ensure that numlock is enabled at startup for faster PIN entering.