An interesting factoid. The Native American Tipi (teepee) was rated by a famous architect as the most efficient portable homes built from natural available resources, ever invented. There are several variations on a theme, such as number of poles used and forming the basic structure. But is a marvel of utility. Cool in the summer, warm in the winter, an adjustable venting system, and the poles attached to horses double as the travois. https://en.wikipedia.org/wiki/Tipi
Bad phasing The increase in depth pressure is not due only to current materials If you are meaning - So practical size becomes an issue - that will still be a practical issue no matter the material Google Hadal-Lander and look at design, size and the space available for people Please Register or Log in to view the hidden image!
Google Hadal-Lander which shows the shape they came up with for exploration Please Register or Log in to view the hidden image!