Wagons and hatchbacks generally have higher road noise levels than sedans, just because of the cavern in back. The single most important origin of that noise is generally the tires.
Tirerack and 1010tires both have good consumer review/feedback sections that rate road noise as one of the metrics. Check out their websites. You’ll be able to select some quieter tires and that should make a substantial difference.
You could also gut the car and install structural damping and matting like I did, but if you were so inclined you probably wouldn’t have bothered posting. It is a solution, but you have to be so inclined.