I think it depends on what you're asking. From my experiences, the size of the IMMstaff over the years seems to wax and wane with time. Sometimes it's very difficult to get anything done. Other times, you might be able to push several things through at once.
If you're expecting NPCs to always be animated around you, then you are asking too much. Most times, however, an immortal is willing to animate a NPC on request. (Note: For scheduling reasons, this may not always happen the day you want it.) And there are times where a member of the staff will animate a NPC without being requested at all. Truthfully, it varies depending on schedules and current staff obligations.
Rest assured, the staff does try to create role play with mortals in a variety of ways, including the use of NPCs.