Hi David,
I am really impressed by how well the raw defaults work across a very wide range of image types, including some really tricky ones.
Try this for fun: take a series of shots of the same scene (say 4 or 5) and deliberately underexpose some and over expose others (use exposure compensation) , at least by one stop in each direction and have one with correct exposure.
My experience is that when I download bracketed exposure images and allow QU to process & create the cache, I hardly see any difference in them on the thumbs and then the images. That's how good QU is at "smart" raw processing, it's more than just a default setting. The refine screen is there to cope with more difficult shots when needed.
Terry