Good game! Some improvement I would suggest is that the ship should have thrusters on side for more maneuverability and the second ship is slow so it didn't felt like I was moving so you can increase its speed.
The issue with increasing the speed of the second ship, is you also need to fight it while you're the first ship. I wanted you to be able to win the 1st battle by being more maneuverable than the enemy, but I didn't want you to be able to win the second battle in the same way.