Good potential.
This game has a good potential, you got the basics and the decent graphics, but you'll need to make some improvements for it to ever have a score over 3.00.
First of all, add the loader scene.
Second, insert quick instructions as of what the cubes are for and what the big ships are.
Some sound effects for shooting and being hit and acquiring cubes would be great.
Make several levels. Maybe distinguish the player's ship in color from the rest of the background.
This is just some advice. I gave the submission a passing score, good luck.