You will need some more ventilation. Ideally you could do it in top portion of door. The overhang protects from rain getting in. I also think replacing that front window with a clear plastic window would give your chickens much appreciated daylight inside.
I also don't think you need a NESTING BOX. You can just place some hay (or nesting material of your choice) into a box, or basket, and chickens will use it just fine. Very easy to just reach down and pick up eggs,,,,, VS reaching into a box especially when limited to crawl into height.