1. picture: Too empty. You could make the temple thingy larger. Also remove the black wall, put something onto the room.
2. picture: Also too empty and the walls look a bit noobish. Put something on the top to make them less boring.
3. picture: The bevel at the bottom of the wall/pillar should be removed.
4. picture: Put some lights in there. And maybe some furniture.
5. picture: Change the texture of the red wall.
6. picture: Some torches might make it look less empty.
7. picture: Quite ok. If r_speeds allow it, you could place a trolley and a bevel around the exit in the wall.
8. picture: The wall in the background looks a noobish too. You could hang some wall carpets on the left wall.
9. picture: Again the walls and the emptiness. More plants could fix that. The two lower windows look a bit misplaced.
All in all it looks like a good start. You should now start to add detail.