That's the feeling I have too. Along with the not remembering books well enough one! I haven't read the Nubian Bradshaws, but they sound right, and the theme is even in Beyond the North Wind to a degree. (WHY are her children's books not better known?!) And yes, Eva Ibbotson -- she does it to the reader a lot, doesn't she? Turning the 'evil wizard' into the sympathetic hero looking for a nice (wicked) wife. Or the lovable ghosts who worry about not being terrifying enough...