Free Days for almost any car class is the benefit I most enjoy. The ability to apply them after a rental makes it even better.
The "Elite" upgrade is called the Executive Aisle. Drive away in a Full-Size or higher vehicle for the midsize price. There is no other complimentary upgrade, so anything else that a station offers/gives you that is not on the Aisle, is simply gravy.
EE pricing for cars in PS is supposed to be lower than any other member group or a non-member off the street.