With its greater seat-to-roof height, no windshield dogleg in your knee's way and a less-intrusive steering wheel, the C2 is less of an obstacle course.
It goes back to the ergonomic design of both cars. For the C1, Chevy chose the highest-performance production sports car of 1952, the Jaguar XK-120, as their model. And like the Jag, the C1 was cursed with a steering wheel practically in your chest and a bolt-upright church-pew seat that had your legs almost straight out in front of you. Neither company dropped the footwells between the frame rails. That's just how it was done in the early '50s, almost all sports cars were uncomfortable. Try a '55-'57 T-Bird and it's the same story.
By about 1960, when the C2 cockpit was being laid out, Zora Arkus-Duntov was on the scene. I suspect his racing background and engineering input was a good part of the reason a Maserati was measured in setting the driving position. The E-Type Jaguar was also much improved, but not nearly as comfortable for people over maybe 5'9". The Sting Ray was built to accommodate American-sized people.