I just finished an 1,800 mile plus road trip and have done 1,500 and 1,000 mile trips as well. I agree with your assessment on a stock car - larger wheels/tires mitigate the crosswind/semi issue to some degree.
The only thing the car really needs for a long trip is cruise control - it just kills my leg after a while.
On the trip wish list: a better trip computer in the cluster and a sixth gear with lower RPMs for level cruising. I shift manually and am always going for that non-existent sixth...