Well, until we know about the leg situation for sure, everything else about the original Space Jockey is pretty humanoid. Two arms, two eyes, etc. and the Derelict had a whole cargo of Alien eggs with Facehuggers perfectly sized for humans - which we know were also able to do their thing to the Space Jockey itself given the rupture in its chest. There are definitely Lovecraftian overtones to the Jockey, but it isn't quite as radical a departure from the human form as it is often made out to be. Which is why all in all I don't hate the Engineer retcon, even though I'd be very cool with a re-retcon that separates the two.
As for the Alien, I find the connotations of David creating and shaping the Alien to be just about as interesting as the ideas presented in the original film, and with the Pathogen in play, there still exists the incomprehensible, cosmic raw material that spawns eldritch abominations behind it all; David, artist that he is, sculpted one particular form and created his "Perfect Organism" and, at the same time, the franchise burst open the doors to explore other wildly different tracks with new creatures, mutations, and offshoots as well.
