Not sure if this has proposed before or not, but here it goes...
The bus idea for stair loading is very cool, but, if it’s a smaller airport where you basically park in front of the terminal, unrealistic. So, what if you could have a point specified ahead of the gate located inside of the building that passengers could walk to instead of commanding them to walk into the bus? You could even model a set of doors that could be fixed liked an entryway and set in the AFCAD so that the people didn’t look like they were walking through a wall.
Just an idea to improve upon and already awesome product!