I used this strategy allot in the second and third mission of the campaign. Not really a victory condition as such, but it can give you a large military advantage within the limited area of a built up star base. I used it as a attack strategy against the "dread lords" in the third mission of the campaign because they were fenced in to one star system but had much better ships than I did. They were also building two types of ship one with 40 missile attack and one with 50+ MD attack. It was quicker for me to research the star base victory than better weapons and defences. What I did was build a near complete military star base within range of both planets and their surrounding star bases. This was the hard part getting 30ish constructor ships into a enemy star system within one turn. All the attack and defence bonuses stack so I decided to add as many as I could even the low level +1 modules. I then sent in my fleets of fairly weedy but fast 35beam 10 shield ships. As soon as my 2 fleets of 4 came within range they had a ridiculous attack value something along the lines of 260 beam 80mis and 80md and defence of 80shield 60pd and 60arm. I managed to wipe out 18 dread lord ships and 3 star bases in one turn without loosing any of mine. Two turns later my troop ships had taken their worlds. After that I realised I didn't need to take those worlds to complete the mission... doh.
To sum up:
Good points:
Major stackable bonuses for your ships in area of effect.
Only really need constructors and a few mid level ships.
Constructors don't have a maintenance fee so you can keep them around doing nothing until your ready.
Speed bonuses for your ship in AOE and speed penalties for the enemy.
Bad points:
If they attack your constructors on route you have to start again.
You have to build and upgrade the star base in one turn or at least defend it as best you can, (18 modules for full mark III)
Limited AOE, meaning you have to get close.
Some modules need extra money expect to pay 300-500bc depending on what you choose.
Will only really work on a enemy that is holed into one system.
I would only recommend this strategy if you need to attack a very heavily fortified system where you are either out numbered or out gunned. This was my first try at offensive star bases but I would use it again probably with less modules I think 30 was certainly overkill.
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