Currently the dropship 1, aka Rasputin, aka Bird, has four usable doors (and four extra windows one can use as doors in a pitch).
Lets make it that the whole side of the shuttle can be opened, allowing mass embarkation and disembarcation.
Benefits (How this will benefit the server and game as a whole):
Obvious marine and alien benefits.
Details (Description of how you think this would work, the benefits, etc):
/-------\
[ sssss ]
[ sssss ]
[ sssss ]
[ sssss ]
[ sssss ]
[_____ ]
Where s are seats and [ and ] are doors, or door that rises.
Think advent reinforcement craft from XCOM2.

As a possible alternative- make one big opening in the back of the bird.
Implementation (Optional, if you have an idea how to implement it):
Rework the shuttle layout.