Its lovely and I'd use the colour of the flowers(not so light and not so dark, that medium pinkish+purplish colour) for the combination or perhaps the light pink if I want more spacious outlook of the room.
That is nice. Agree. Keep it light because that will be the main feature. A light subtle lilac should do. What kind of flooring do you have? If you have wooden floors, it may be nice to do the walls white.
Why don't you take a sample of the wallpaper to B & Q. They can find a suitable shade for you and even mix colours to your requirement.