I think the ship interior is fantastic. I like the alien planet. And I like the crew. I find them more believable than the people in (for example) Star Wars or the Matrix, or any of the other top SF films.
All in all, I think this is the best SF movie ever made. There are a few bits I think are disappointing, the worst being when the little alien scoots sideways across the table like an aggressive shaved teddy bear on castors. I'm afraid I laughed out loud at that one last night.
Seeing it back on the big screen was almost like stepping into a world you have imagined, which has now become real.