S.H.
love color questions!
(sigh) great color combos. I like a lot of color & variety. I try to avoid matchy-matchy. Sooo, my thought would be: don't try to match. Choose a 3rd color for the walls. Add a little bit of it into the quilt/bedding...even with throw pillows.
I would use a citrus yellow/green. Something lighter than the green in the quilt. The reason for this is that purple & yellow are opposites on the color wheel. By using a yellow/green (think Crayola colors & citrus colors), you will make the predominantly purple quilt "pop" against the walls. The green in the quilt then becomes an accent....& is also an analogous color because it is next to the yellow on the color wheel. Easy-peasy way to tie it all together.
Soooo, using your ideas, go for the one which will provide the most light for the room + work with your wood tones. & I will be honest with you: white or very dark wood furniture will work better with purple. :)
With this in mind, go for a white canopy....white wainscoting....with the yellow/green on the top. Match the curtains to the canopy. All of this will help brighten the wood + purples. & by using some purple/greens in the artwork, you will bring it all together. You could also use pops of the yellow/green in accents on the furniture....the lamp, etc.
Oh, & for the curtains....another thought: if you can't/don't want to match the canopy, then you could use more of the quilt on the windows....going with patchwork or one of the fabrics. Have Fun!
EDIT: http://www.houzz.com/using-purple-green-%26-yellow. Love the yellow with the purple.
http://www.houzz.com/purple-and-green. Look at how the green pops against the purple. I think you should avoid purple walls with the purple/green quilt. It will blend in too much.
http://www.houzz.com/photos/bedroom/purple-and-green-. Interesting how they used a deeper red for the 3rd color. I didn't think of that one!