Keep the car. You have a manual wagon. Keep it in good shape. Do all the maintenance, Keep all of the records. Get a APv2 and flash stg 1. You'll have a renewed joy for your car.
In a few years after you've paid off the car, it WILL be worth something considering you've kept it in good condition.
As you've discovered, performance manual wagons have gone the way of the Dodo. Maybe by the time you're finally ready to sell, CTS-V wagons will be in your price range.