The Anesidora is quite different and I guess borrowed a lot from som early Ron Cobb Design.
It feels more modern, like a bridge between the nostromo and the high tech prometheus ship.
It's very nice if you ask me, Creative Assembly definitely have taste. They made no mistake on that I think.
I believe Sevastopol is much larger too. Probably due to the fact there are civilians living there which I guess was never intended for the nostromo mineral hanger or whatever you wanna call it.