The fact of building small ships and compact ships is that you need to get within small spaces, and sometimes, these small spaces require some real fiddling with your jetpack on planets, which depletes your hydrogen fast.
If we were to have crawling, our camera could be directly on the floor and we could reach up under something, with the hitbox being closer to the ground, like an army low-crawl
One way that the feature could be prevented from looking ugly is if the jump button would flip the astronaut on his back for 75% of the crawling speed, but allowing slightly tighter spaces to be fit into and allowing you to look above 45 degrees upward, and then moving that previous point to your highest camera angle again, but you now can look forward as if you were looking straight into the sky.
normal WASD would be the same direction on either side, belly (or hands and knees) or back, allowing you to not disorient yourself, as W becomes up and S becomes down, whereas A and D become shift to left and right respectively, in relation to your character model. Reason being, your typical forward, if not the way you are facing, is regarded as headfirst, and your typical reverse or backward is usually feet first, hence falling down as a relative to the gravitational grid and jumping up the opposite of that. when you face the ground, you tend to look "forward" keeping your same direction, and when you flip on your back you tend to want to move in that same direction. For example, working on cars (new, old, prototype, etc.) your "getting back out" is just that backwards hence the S key, and you typically dont turn around underneath of a vehicle because its far easier to reverse your direction and go feet first out into the space beside the vehicle, wherever that may end up.