SimSpace: Feedback time! Thread

Hello you glorious gamers. I have been working on a space shooter, that I'm calling "Sim Space" for now.

Game description:
"Sim Space: Combat is a slick top down shooter where you duel against devious AI enemies. The game centres around staged arena based combat with a simplified upgrade system that allows you to tailor your ship to your play style. Opponents will do the same and try to out-do you with their own favourite equipment combinations."

Now I have got to my first Alpha stage, where I need feedback on the moment to moment game play, controls and general impressions.
Now the AI is not up to scratch, they are as dumb as posts at the moment, but still pose a fun challenge. Doing the AI for this project will be the most time consuming part - so before I do that I need to know if the game play is right. (If I change the game play significantly I'll have to re-write the AI loosing all my previous work)

Here is a link to the game:

PC: Utilityfunction.co.uk
Android: Utilityfunction.co.uk

Here are some screen shots so you can have an idea of what it is like...

Notes:
PC controls:
Movement: WASD
Fire1: Space
Fire2: R
Fire3: F

The game is intended for Android so I would prefer if you tried it on that.

Thanks!