"I think it really shows through that there was never a plan with any of this."
I've been leaning that way for awhile myself. Quality over quantity. Prometheus should've been the only prequel. They had the right looking planet, and a crashed juggernaut. Change the planet name and some of the characters/events, run it at a healthy 2 to 2.5 hour, lead straight into Alien 1979, and boom.
But it's a business, and it's the age of the "trilogy". That's the road they went down, and now they're lost in the back-country. The studio should have A.D.F. meet with ridley and discuss what was wanted for the third movie. Have Foster write the thing in all its glory. No budget issues, no time limits, no cut footage, no editing problems, no compromises. Then green light Alien 5 for 2019 and let's move on. Movies are a business, films are a product. But at it's core, it's still art, so limit yourself as little as possible. Which is why I say give this particular storyline to Foster. The man does with ink and paper what directors like Ridley and Cameron do with film. He's capable.