I couldn’t help myself and started playing around with a few of those shapes to see where it can lead when I add some shading, colour and detail. 

Here’s one of the ships taken from the tutorial:

It’s still vector shapes and you could make it smoother and lose the vector feel by adding softer shading and some dirt and grunge overlay in the bitmap tool – but that’s a task for another day.
Once scaled down to a more game friendly size those edges tend to disappear: