Wow, shades of purple and orange would make a beautiful bargello quilt if you ran colors kind of diagonally from light purples to dark then, somewhere around mid way across the quilt top, begin with the shades of orange and go to the opposite corner. Maybe some of the Jo Morton cinnamons would work in with the orange colors. Or maybe just do a sampler and use bleached muslin for the 'white' areas.
Katier825 has a pretty Lucky Stars quilt idea, too.
Maybe if you think 'shades' of purple and 'shades' of orange and the colors won't sound so wild. Good luck whatever you choose. Please, post a photo when it is finished.