Defending Avaria (IDEA)

I was thinking about writing a sci-fi story about a group of soldiers who lived on a planet that they had to defend. In this story it's in the future so they have space ships so the people defending this planet live in a spaceship orbiting a planet named Avaria. (UH-vare-E-UH). This is a one of the few planets that humans still control.

Background
I thought i would through in a little background of the story. This story takes place in the year 4,437. The humans have left Earth to find more planets to colonize and only a few decided to stay in their own solar system. The idea seemed fine to everyone. Just move into another solar system where life can survive. After they colonize one planet they had to colonize them all. Soon every planet that could support life in that half of the solar system had now supported life and each had trillions of people living on them. Then one day an alien race had rose from a planet where humans had already colonized. These aliens were the first sign of intelligent life humans had ever came in contact with. These aliens had been hibernating for millions of years with trillions of weapons and space ships stored throughout the universe. These aliens had destroyed all other forms of intelligent life in the universe other than humans. Once the aliens awakened they started to find all their ships and weapons and went to war with the humans. Since they had no form of defense the aliens had killed of thousands of earth planets. Only the farthest planets like Avaria which is similar to earth except there are no deserts or giant mountains. The humans quickly designed a defense system for Avaria. They knew it was not enough to stop the aliens but the system was supposed to hold them off long enough for everyone to escape. This story is about the people that must sacrifice themselves for their species to survive.

The humans have no place to hide except earth which they abandoned so long ago that no one knew where it was. The humans must find earth where their old defenses could stop the aliens.

That is the background to my story.

Characters
The captain (Needs a name) (Around 47)
His wife (Needs a name) (Around 46)
Their son (Main character needs a name) (Around 17)
The aliens:the aliens use their hearing to detect anything and everything they want to within a very large distance. They are like hawks but more colorful and tentacles coming out between their wings. Their only weakness is being frozen and underground fighting.
Queen Avaria the 8th. (Around 40)
Shotty: a soldier and friend of the main character (Around 19)
Avena:Stragegist and teacher to main character. (Around 17 years old)

I want to know what you think of this idea and if you think of any names for the characters please tell me. thanks!

btw the name is defending Avaria