I am confused as to what makes it "uncomfortable" The seats in my Gen3 were extremely uncomfortable the entire time I owned it. I always joked toyota made the seats so uncomfortable that you would not want to make any trips in the car - hence lowering your overall gas consumption. - The PriusC seats are so much more comfortable than my Gen3 seats were - and the smaller size makes it easier to drive - can not argue with the cargo space, but if you haul a ton of stuff, not sure why you would be driving a prius anyway.
Once I learned how to adjust my mirrors properly the blind spots in my GenIII went away and the backup camera covers the rest. I recommend everyone do this.