No, don't wait. Extra foliage will help her feel more secure. However, if possible, try to get a live plant instead of a fake one. If you have the correct grow lights, a live plant will be more rewarding for both you and your chameleon. I do know that it can be hard for some people to find large, live plants, so I can understand you getting a fake plant.
Does her cage face out a window? I once had turkeys jump on my neighbor's roof where they were visible to my jackson's chameleon--he turned ghost white. Seeing any type of bird could trigger the fear response in a chameleon.
Also, it's hard to tell, but have you covered all sides of the cage except the front? If so, good. Doing so will help her feel more secure.
I'm on the same boat as jacksjill, I'm not too concerned with her coloration. As long as your husbandry is correct, and you provide her ample foliage to feel secure in, then there is not too much to be concerned about. She will get used to her environment and become more confident when she realizes that not everything is going to kill her.
I might add that chameleons, some more than others depending on personality, can be very sensitive to the color shirt that you wear in the room. A lot of my wardrobe consists of reds and blacks which my cham seemed to react to. I would usually walk around my room without peering into my chams enclosure. And right before leaving the room, I would sneak a quick peek, only to see him displaying "stress colors." I thought that I might have been doing something wrong with his care, but one day I walked right in and saw him wearing his relaxed greens. And as soon as he saw me, he started changing his colors. After that day, I went out and bought an oversized button-up shirt that I would put on over my clothes before entering the room. Since then, he has never displayed those colors once he has spotted me. He would still be uneasy and show slight stress marks, but not to the degree as he was showing before. My jackson's used to be incredibly shy, but now he is very comfortable with me wearing any color shirt.
When you walk into the room and see her, do her colors change significantly in the following minutes? She could just be very shy.