I'd also like to hear more about the thinking behind those sloped ledges.
At first glance, I thought they don't look like they would be comfortable for the snake to rest on. Gravity will try to pull them off. Then, I realized that snakes have a much lower center of gravity than I do, and they have belly scales that can grip that rough surface almost effortlessly. Still, I'd like to hear your thoughts on why you designed them that way when a flat surface would be even more stable.