Can't be impeached because presidential impeachment has been a dead letter since parties came into existence.
Can't be disqualified from office.
And can't be prosecuted for crimes committed under color of office.
...and to hold this office the only requirement is age, citizenship and popularity. Felon? No problem! Have financial issues that make you a security risk? COME ON IN! And now he can shoot someone in the streets of Manhattan and SCOTUS will say it's an official act.