You should be able to get a sense of scale for the scene without have to add other items to it.  Consider showing scale by including elements that have recognizable scales such as doors, windows, ladders, gangways with railings, stairs etc. 

2 or 3 rows of widows on some of the walls can go a long way to show how large the walls really are.

 

For me personally when buying Poser scenes it’s a matter of is something that would take me a lot of time to do myself or is it something really unique.  So far for me your Landing Bay doesn’t meet either of those criteria.  I do consider myself a decent modeler, texturer and rigger so I may not be representative of the typical Poser buyer.

Chris Cox