I was just revisiting the the DS9 episode "Melora" and it got me thinking about how the episode makes Starfleet seem somewhat less than accomodating aliens with unique life support requirements. It seems odd that the Melora character had to struggle to live in an Earth normal environment. You would think that Starfleet would have special training and ships specifically for crews from low gravity worlds. The episode gives the distinct impression that her species does not leave their world because of gravity concerns. It seems that these people would be ideal zero-g engineers and are perfect space explorers given that they are naturally adapted to the environment.