Prometheus is probable one of the Best scifi movie we got in years but its a mess made of the different scripts and on set last minute ideas.
Ive read both released scripts and they are far more satifying than the final movie, they are very close to the movie but the devil is in the details they feel less dumb or rushed the ideas and concepts were awesome (the way engineers see, the different creatures, the more mature holloway...).
To me Scott managed to make every bad choices possible scriptwise when it came to shooting (thank gods he did not go with the egyptian take on the engineers with their pyramids and djellabas or the obvious and almost embarassing 2001 ripoffs) BUT he's Still one of the master when it comes to direct and production design.
If you like Prometheus in some way but were disapointed nonetheless i advise you to read both scripts by spaith and lindelof both are great reads they Will help you make sense of the supposed "mysteries" of the movie ( wich are actually left overs from the scripts, Scott removed on purpose key dialogs to make it more mysterious ohh haaa and set up the sequel).
And yes you must buy the bluray just for the making of FURIOUS GODS wich is great