I thought the same with the Mustang - same "tub" feeling but not quite as bad. I've never felt like that in a Corvette or other even sportier cars. GM gave up to much practicality for looks - nailed it for their existing target audience but forgot to leave room to bring in new customers.I didn't know I was one of them until my son was looking for his first car. We were in almost everything, using elimination. The Camaro was terrible. I HATE that sitting on the floor with tiny windows at shoulders................ so yes, claustrophobic. I like light in my vehicles. Other than summer, my BAMR roof shade is always open........... for the light. So, the Camaro was terrible, and the Mustang was slightly better. Liked the look much more, and probably could live with it, but HATED the distortion of the heavy sloped rear window. The Camaro had that problem also, but I was more busy trying to figure out if I was in an accident, if they had airbags in the top of the doors.................. to cushion my head. I'm not short for a woman either (I'm 5'7"), but I'm all legs.
At the end of the day, part of the reason Corey went with the S3 was due to greenhouse, outward vision, and great interior. It made fun driving more fun. He is 6ft, but has long legs also.
As for getting used to the vision, the thing that the powers that be forget about, is that you have to get someone to get in the car and drive it first.............. before they can get used to it. Short of Camaro diehards, a lot of people I know looked at one, said "nahhh, transformer," and moved on.