sea surface glider

This would be a tadpole chasis would make it the fastest vehicle in the game above the surface but slow in the water. In addition it would make a high amount of noise and if the chasis goes below 200 meters it takes damage. and would attract any nearby leviathans. however its speed makes up for most of these cons. This should be somewhat balanced and since the map will no doubt be the biggest in any subnautica game this will allow somewhat fast transit around it with suitable cons to keep it balanced.