I go with a Custom Race with super breeder, max population growth, max moral, max econ, luck, creativity, and 10% soldering. I use the Dreangin tech tree. Go right for recruting centers and watch your population explode, this combo is really easy to get a econ going very early and it only gets larger from there.
After the econ gets going I tech right to the evil beam wepon tech (Dreangin get this very early) and produce a few hard hitting light fighters to ward off any comps looking to go to war with me, after that is down the planetary invasion tree and my path to galactic domination
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Its also good to note that the Dreangin tech tree can produce sickly military production, AI's will be hard pressed to match the speed at wich you can build ships without bankrupting their empire.