there was no wondering left

After the creator (engineer )threw himself to the water, the movie should have continued with the Prometheus spaceship scenes suh as; the human robots (each crew member should have had their own individual human robots as their assistants) should have watched their new employers' (the crew members') dreams to know them well.We could see some archaeological stuff in one of a dream as well and we could start wondering why an archaeologist exists in a space ship. This crew should have only known that they were on this journey to discover new life forms in a remote planet. So that, by the discovery of the sculptures of the human heads in the cave would make an amazing effect both in the crew and the audience. Since these people are scientists, I dont think they would be so stupid to take their helmets off and bring the dead head of an alien inside the ship(viruses, bacterias and other kind of disease danger).Thats why they could build their own shelter inside the cave. When they found that there was human DNA and head inside that alien helmet, the audience would get another shock as the crew would. When the anger and wonder rises up among the crew, the old man (Guy Pierce) would show up and tell the crew the truth why they are there with the help of the explanations of archaeologists. Instead of the crew discovered that it is a ship that they found in that cave was targeted to destroy the earth( which makes no sense), the crew should have discovered that this ship is a laboratory where the new species were created and some of these creatures began killing the 'engineers' there.So that, the deaths among the crew members would make a sense instead of looking like cheesy alien movie serial dead. The last creator (engineer) alive should have had a touchy moment and be honored to see what they once created have come to this planet and brought him back to life.When he was asked 'why did they create human being?', his answer should have been ' I am just an engineer who was told what has to be done here.You can find your answer in my mother planet where I come from'.Then he should have sacrificed himself to save our girl from the aliens after he told her how to go to his mother planet.Then we would have seen a space ship flying off in the air instead seeing the the birth of 'Alien'. The existing scenes would look fine in m storyline. Please comment what you think of my storyline.Wouldnt be more exciting and wouldnt this line make the movie an epic one?