One key thing I think Alton should do is sit down and watch a POV of Alien Encounter, one thing that sticked in my mind from the pov was the death of the maintenance worker, the fact the audience was their helpless strapped in hearing this man being killed and the water being the "blood" pouring down ontop of them must of been terrifying. Thats what I want for Sub-Terra, I want the egg to come out and take one of the phalanx and drag them underground, you drop, and the audience hearing the screaming of the phalanx operative and crunching of bones before being risen back up.