Here is my suggestion for the ramps. See that vehicle spawn area? That thing is going to have to be at ground level no matter what. So if you could have one of the entrances run along parallel to that, you could reduce the number of places that *have* to be above ground from 3 to 2.
Making the vehicle ramp steeper will also give more wiggle room during placement.
For the other entrance, you might want to consider having the ramp start a little bit inside the building to give you more height without changing the area of the building.
The vehicle ramp does start inside the building. It’s unseen in this shot but the ramp starts at the edge of the vehicle pad itself and the dark sides are more guide rails when exiting. The ramp extends down for a while to the skirt and is at a gentle grade.