Ideas: More Ideas for the Plot

So far I came up with three ideas for our B-movie, the first is about a mutated astronaut, the second was an alien parasite the possess people and uses them to lure in victoms to eat and the last idea is about a space criminal with shapeshifting abiliteis landed on earth and started to feast on the people around it.

First I will explain my idea for my mutated astronaut.
The first act begins with a group of astonaut going into out of space for several years, while that happens the narrator is talking about how brave the astronauts are going to an unknown planet.
Few years later the space shuttle that was carrying the astronaut crash lands on earth and nasa with the military came rushing in to see if all the astronauts are okay. When one of the armymen opend the space shuttle's door he only found one astronaut. The head of nasa asked the astronaut what happend to the others, he responded by biting the army man that found him.
Second act begins with the military keep the surviving astronaut a secret by saying that all the astronauts in the space shuttle are dead. While in reality the surviving astronaut is locked up in confinement while the other people from nasa are examinating him.
While in confinement the astronaut is going through changes, his skin is falling, his nails are longer and his shape looks more skeleton like. Suddenly the astronaut started to dissappear and has superhuman strength, he then escape from his holding cell and started to slaughter everyone, but not before one of the armymen calls for backup at the military. This is then turned into a hunter verses hunter when the military sent in a few of their best teams to go inside the nasa building and hunt for the astronaut, at the sametime the astronaut is picking them off one by one until there is only one army man left inside the building. It is now a stand of between one army man and the mutated astronaut, luck for him the astronaut is covered in blood so the army man can see him. But the astronaut was too powerful so the army man decided to sacrifice himself by lodging a grenade in the mouth of the astronaut in hopes that would kill him.

My second idea is about a meteor crashes on earth. Somebody went up to the meteor and examines it. The meteor opens up and a small alien jump out of it and insert itself inside the human and took contral over him.
The alien uses the human to lure people it secluded place where it can feast on them, and if the human body out lives it's usefulness then the alien jumps into another persons body to lure more victoms but not before eating it's previous body.

My final idea is when a shapeshifting alien from out of space crash lands on earth and started killing people while on the move. At the same a team of police officers from out of space are following the criminal and they also can shapeshift.