I have heard plenty of non fans complain how short the life-cycle was in AVP, you don't need to be a fan to watch all the movies or understand the lore. As I said though, some probably didn't mind it.
Quite a few things, though the Alien does take it to the extreme. I remember that some ants have acid in them, you got eels with double jaws, parasites that incubate in hosts, insects with exo/endo skeletons. The Alien borrows from a lot of earth species and who knows what life is out there and what form it would, some of the alien traits are possible if unlikely.
Rapid growth would be impossible, especially for its size and complexity, both host and Alien would cook if they grew in minutes or seconds.