SpaceShooter

So I am working on a space shooter with a buddy of mine, I am doing the graphics, while he does the coding.
Problem is, I've never really worked on a space theme style ever, so I may need some critique.

Here is just a generic space background I made, I will expand up on it by adding more so the screen can scroll and display new objects in the background. Here's also a font and a border I made, not a whole lot here really.

And here are the ships, the ships on the left are the playable ships, on the right are some enemy ships, and asteroids.
And at the bottom of the playable ships are just two small tests, a Galaga ship, and an Arwing.

And here's just a sample animation.