4. Questions Answered
This is a big one because the Alien franchise has enough unanswered questions lingering around to make 10 films. What is the space jockey? Why are there facehuggers aboard his ship? How did he die? How did he end up on the LV-426? What exactly are Weyland-Yutani's motives? How did they find out about the existence of the Xenomorph? Those are just a few questions posed by the first film. The list goes on and on but if Ridley Scott were to return then he could make a prequel with a solid background in the origins of every question and tell one sweeping story that interconnects them all together. I know that sounds much easier said than done if you can answer one question than the rest will fall in line.