Do your rooms have an identity crisis? While living in a home, we often transform rooms in to areas that suit a different purpose. I've seen many offices in dining rooms (mine happens to be in a bedroom!). But when you sell, you should stage your home returning each room to their original intended use.
This Family room is also being used as a workout room. 
And this family room is being used as a craft room:
You might be surprised that some buyers are not imaginative. Not using space as it was intended may give the impression that the house is missing something or not laid out well.
When I stage, other than an occasional office/bedroom, I make sure that rooms return to their original function. That way, you won't confuse any buyer and they'll be able to visualize their own furniture fitting into the room.
