In Zach's and DST's defense for this, at the panel at C2E2, a question was asked about the difficulty of getting actor's likeness rights for the figures and Zach said that they don't need the rights because they are making figures based off of characters, not actors.
That being said, I think the Ripley figures are perfect, because they look like Ellen Ripley, not Sigourney Weaver. Dana Barrett is different because I can say that she needed more Weaver likeness for her character.
I'm not saying that all you guys wanting different heads and hairs for your Ripley figures are just plain idiots for not seeing this, I'm just making it clear that DST does what they need to and very rarely does it not work.
And for the record, I would also love a longer hair piece for Alien Ripley