Besides, when you see the "classics" in Sci-Fi, you'll see that the design of spaceships differed according to the era when those movies were made.
Do you prefer the Flash Gordon look, or the Forbidden Planet look, or...well, you know what I mean, it's up to the designers and artists + the Director's to set up the feel of the world they want to portray. Who knows what will be on screen 20 years from now:unsure
We will all be flying around in big eggs. LoL