Okay criticism time!
The doors are too small compared to the scale of the room. Unless Mario lives in some refurbished barn or something, I don't understand why the rooms would be so high up. Also, the shower doesn't appear to have any depth at all, and looks more like it was painted on the wall than anything.
This is good and you filled out the space nicely. However, I have to mention the doors again, because they are completely out of scale with the furniture / windows. The Wario faces on the couch are a neat addition, but they mess up the outlines of the cushions on the inside of the couch (you can notice how the black lines separating the cushions go - - - ). Also, the shadows behind the posters look very awkward. Considering that a poster is taped ONTO the wall, a shadow behind it to indicate it is relieved out FROM the wall doesn't make sense.
Not much to mention with this one; then again, not much IN this one. It's pretty empty and I think it could do with trees / flowers / patches of long grass or something in the yard, in order to fill out the empty space.
These rooms you've made are good, but they can most certainly be improved on.