I see what you mean by the first 2 things especially number 1. As for your third point I have to disagree and tie it into the 4th one that no her time as Robin really did not matter in the long run especially to the family and myths as a whole. Also while Dick and Jason's new roles may have eclipsed their robin role( which I think can actually be argued against in some cases with Dick), it was the Robin role that defined their relationships with Bruce and made their marks in Batmans history. Robin ( especially the father/son/ mentor/ partnership)is important and needed in both those histories where it isn't so much in Stephanie case. She could go straight from Spoiler to Batgirl and keep in her problems with Bruce without that stupid baggage that her Robin storyline had.