I understand the need for making things look better or adding chairs that an entity could actually sit in. Honestly, I would like it so that when I am playing with friends, that they can climb into my spacecraft and sit somewhere without being able to affect my ship. Currently, if I want them from point A to point B, without waiting on them to create their own ships... they have to get into my ship and get in build mode.
Back to the topic at hand. Fins, wings and other aesthetics, are just that... There\'s no air-resistance in space, so fins, wings and other devices made to move an object around tighter corners is pointless as it\'s air that causes this resistance. Literally, you could be a floating rock in space and it would move just as quickly as something aerodynamic. It would be purely for looks or as you said, flair. Either of which, isn\'t necessary in the beginning mechanics of the game.
Perhaps, if there were more realistic atmospheres on the planets or air resistance there, I could follow your point. As landing from space to Earth, you would need an aerodynamic space/aircraft. But, the only thing that planets currently have are gravity. Think of the moon. The mass of the planet is large enough for an object to float towards it, however there is still no air.
And while I can see this down the future... currently, I feel that this should be closer to a last on the list sort of thing, unless however there becomes a need for such triffleries. :P