I think Elizabeth was someone who has been much malighned with little reason, as anyone with many unmarried brothers and sisters would have tried to well by them after being elevated to such a position. She had family loyalty, and that is a virtue by most people's standards, although nepotism isn't at all. She certainly was a stunner, and would have had to be to keep Edward's interest.
She seems to have been someone who could be soft as well as hard, intelligent as well as seeming this dumb, widowed, relative commoner the king shoudn't have married. That is how she was seen by some. Most of her descendants with Edward come from Elizabeth, who married Henry VII-certainly most modern royalty can trace their bloodline there. In light of that, it certainly is interesting that her other children didn't leave that many descendants.