Not having a go, you have a valid opinion and it didn't meet you expectations, thats fair enough, Spielberg's War of The Worlds is the same for me. Just want to clear up a point, though -
3. Charles Bishop Weyland and Bishop II are identical despite an age difference of over 200 years?
By Bishop 2 you mean the guy in Alien 3 or the artificial human?
If you mean the artificial human, the answer is obvious - its only modelled on him, but even so there are heaps of examples that every number of generations has someone that is uncannily alike to another. My father is the spitting image of one of our family's medieval relatives. Its not so strange.
As far as the gestation goes I just put that down to these people being healthy, fit hosts and not malnurished skinny space jocks living on protein mush.
For the longest time people ask why do Aliens always stab the brain with thier proboscus and leave the meat, why not eat it? The explanation most widely accepted by Alien fans is that they require a certain portion of the brain, a certain enzyme to survive, they are not complex beings, more insect than anything else obviously, does everybody here share that explanation?