I had a small Idea where the first prequel would focus on a group of people in a research outpost that happen upon an alien egg. The main character gets hugged, and the crew manage to remove the chestburster before it rips through the character's chest. They try keeping the Alien captive, but it escapes and hunts down the crew. The small catch being that it recognizes coming from the Main Character, and takes an interest in her, toying with her throughout the last act of the film before becoming frustrated and bored and finally watching her kill herself.
Kinda lame and unoriginal now that I'm looking back at it, especially in such a short summary. I'm one of the people that feel a prequel is unnecessary, especially if it still shows off the Aliens in a Aliens/AVP fashion, where they aren't intelligent and die easily.