Personally, I find the window ledge one of the most comfortable arm rest's I've had to date.
With that being said, there are products that create a better pad/rest on the driver's door. I can't agree that it'll look good, but its your car.
2011 JGC WK2 - Laredo X - 5.7 - 4x4 - 430N(RHB)
2010 Audi S4 - BMW 1150RT (Mine) - BMW 1200RT-P (Theirs)