Padding the seat to be flatter may be an option, but be careful to what extent you change the seat.
I sold VW's for 6 years, and have owned them for the past 30, The official word from VW is that the seat is made with a higher front to help avoid sliding out of the seat in the event of a frontal crash. The slight angle in the seat helps hold your posterior in place thus anchoring your body more firmly so the lap and shoulder belt can handle the load more efficiently.
Also, by changing the seat, by either using one that wasn't made by VW, or one specifically made for the car pretty much leaves your on your own in the event of a seat/ accident related injury. You're potentially changing the anchor points, engineering, etc that the factory designed into the seat.
That being said, For those of us who are a bit wider than the bolster allows, there is comfort in the fact that the bolster does eventually loosen up a bit and shapes to our bodies.
The complaint I heard more than others, and what sort of bothers me about mine is the non-tilt head rest. It seems to push your head forward when the seat is in a more upright position. It can be taken out and turned around, giving you an inch or two of relief.
