About the holograms and such:
I'm pretty sure Scott is only counting his original Alien as canon with Prometheus, not any of the sequels.
As such, remember that the Nostromo was essentially a mining/transport ship, whereas the Prometheus is a heavily-funded research vessel. Of course the technology onboard the Prometheus would be newer and more expensive than the technology onboard a ship whose sole purpose is to haul shit from point A to point B.
And if Scott's Alien and Prometheus are the only things that are canon to Scott's universe, then technology depicted in Aliens, Alien3, and Alien: Resurrection, as well as the AVP movies, don't factor into this discussion at all.