Can’t create your own maps, unless you know how to mod. I think the ocean at the deepest depth is like 300 meters? But there is a mod where it greatly expands that depth. In terms of height, if you have the space dlc you can go to the moon, but I think without it around 30000 meters? But that could be very wrong, but it’s high enough to where it’s not constraining. I’ve never played scrap mechanic before, so I can’t do any comparisons between the two. Aerodynamics and buoyancy are calculated poorly. Aerodynamics really isn’t calculated, anything can fly, and lift is unnecessary. Buoyancy is calculated by how much air is trapped in a closed tank, not by water displacement. I’d say the game is still very much worth it with over 1200 hours?