I liked the color scheme and the simplistic pixel sprites.

You could have added some kinda sound effect when you blast an enemy ship.
And to me it looked like the missiles don't tend to come in contact with the enemy ships, it looked weird to me because it seemed to like hit an invincible force field before exploding.
You could also add in some weapon upgrades, and the movement should be restricted to only left and right like other space shooters.
But if you think that the concept of moving in any direction is better then i suggest putting the ship in the middle when the game begins.

Also you could add in a leader board and a point system using a counter for every ship destroyed, it makes the game interesting.
It is just my opinion.
And like the other person said, The game doesn't stop even after death.

So remember A for effort buddy.
Good Luck further !

Decent, I wouldn't say it's fun but that's more opinion than anything.
The automatic spam fire is kinda over powered and the dying in one hit doesn't really balance that it just makes it broken in both directions.

Decent Concept. Game doesn't end when you die... Interesting....