Nope. I've played Morrowind, Oblivion, FO3, and FONV and have never lost a character and have never overridden a save that I didn't want to.
Bethesda can't account for your siblings overriding your save games.
Separating characters like DA:O is accounting for your little brother, or big brother. Plus I hate scrolling through my 50 saves to find the one I want.
Bethesda, please separate files based on character. That way I can have as many branch saves as I want without having to deal with other characters getting in the way.