Building on what GTEASER suggested about letting the fuel pump prime for a bit- how long do you generally wait between turning the key to the "run" position and turning it to "start"? Not that a 2007 Focus has much in common with the 5th-gen Legacy, but a friend of mine had the check valve at the fuel pump go bad, which resulted in the fuel system losing prime when the car sat for a while. Started hard if you stuffed the key in and immediately cranked the engine over, but if you stopped at "run" for a second or two, it fired right up.
In that situation, the solution was to do nothing, since the check valve was part of the fuel pump carrier (and, therefore, expensive), and they were already shopping around for new cars anyway. I would assume that our cars have a similar check valve, probably also integrated into the fuel pump carrier (and, therefore, expensive), but I guess I don't know that for sure.