I would have to agree on that point, Sigourney Weaver is what made the alien films effective. Yes, they could have finished off the series a lot bettter than they did, but that's the way the cards were delt. However, they should at least have her in the next Alien to either conclude the story line forever, leaving open the possiblity of another hero or herorine to take on the franchise. A guy could take over but they would need the character to be an unlikely hero, someone who is set up to fail but manages to defeat an alien. Hence, that what's made Ripley such a cool character.
