I feel that architecture in third-person computer games is just large in general. I think this is because the camera is usually floating significantly above the character's head, and having the camera brush the ceiling of a normal-sized room would make it feel small. Another thing may be relatively coarse collision boxes and characters defaulting to running. You need to have ample space between furniture, and then you have to increase the room size or you can't fit a normal-looking amount of furniture in there.