Now remember what I just told you on the other threat. Think shapes as you create. Also this is isometric art and scale is very important. The floor wood planks are much too wide. They are half the width of the door. Isometric art also never has skies. Why, because you are looking down at an isometric angle. This means working that sky as a treatment not an environment.
You have titled this 'Starry Room', go from there. VanGogh has a painting called Starry Night (google it) maybe you can make a room based on that.

You might also visit all the floors of the Joint to see what works and what makes rooms interesting.

go!