I fail to see how it looks more advanced than this:
In this regard, I think the nostromo actually looked more advance than many other ship.
The sulaco looked old (but practical for army).
The only thing that stood apart are the switch and buttons and all the technological "integration".
But it's really nothing major, most of the designs felt very advanced and yet practical in Alien.
What didn't feel futuristic are hanger, vents and many places where it's not supposed to be nicely polished and shiny. I think it's rather coherent as a whole for now. There may be different ship constructor and models too. Each one having different engineer/architect. Although, I do regret a lot of "clunky" aspect of the exterior of the ship and the smooth/round/fluffy aspect of the inside.