Hello BCFRS and welcome to our forum ..........
The only thing that I might suggest, would be to get a seat pad that would fit just in the center section of the back of the seat.
That may position your body "away" from the bolsters far enough that they won't bother you.
That worked for some folks over on the Miata forum.
NOTE: I'll call on our resident "big guy" @
Ultramaroon for his input (although, I'm not sure he has an "athletic" build) .....
humfrz