Alien 3 had a great plot. However, the script was horrendous. If you watch it, please watch the Assembly Cut. That version is at least a complete film.
The concept of a group of prisoners on a correctional facility planet who found redemption by trying to kill the Alien with little more than kitchenware and burning lead was a great premise. It was uniquely different from Alien and Aliens in this regard. I also appreciated Alien 3's relentless environment.