These are 101 things and you are well into the 401 things, but from your OP it sounds like the car ran fine one day but not the next morning. It also reads like you were away and it was not parked in your garage that night. What else could happen overnight? Not sure where it was parked, but did a mouse build a nest in your intake to the air cleaner box? Did an animal chew through some wire insulation somewhere? Could a vandal have poured something into the gas tank?
Other 101 things: Ensuring your throttle linkage has full motion and that one of your throttle rod ends did not snap apart, and ensure your VVT solenoid isn't stuck.
Not a 101 item and not likely to happen overnight, but maybe a compression/leakdown test and/or visual inspection of the valve train might reveal something.