Ok I happened to take over the planet Mafi. The Planet is high in Metal Deposits and is neccesary for a defensive barrier.
With the marauders help, I was able to overun their defences fairly easy. I am also one planet away from taking over all adjacent planets to complete my defensive barrier for my homeplanet. It should be fairly easy, considering that it only has half the units that I have to attack.
Here is the current positioning of the enemy and me:
Current Standing FleetFighter MK I - 150
Light Starship - 5
Raid Starship MK I - 1
Raiders MK I - 425
Missile Frigate MK I - 15