I would definately ask the customer more questions?
I would find out the purpose of the quilt? Does it have to any thing to do with school colors, etc? I would come up with several different patterns that you could easily get done and ask her which one she prefers. I would even have her help to select the fabric.
Purple and orange...I too was thinking fall leaves colors. There are great batiks that work well for this. I was also in agreement with someone who mentioned the Day and Night pattern. There are several pictures of others who have made this quilt pattern that are posted.
If you're like me the decision process is always the hardest as I start and plan a project. The reason is that I like too many different colors and patterns.
Good luck and keep us posted with pictures with your progress.
Pam M