Grab a second tech levels in missiles, then get point defence (under military science).
Now you can go for beam weapons. I suggest DepletedUraniumCannons (cheap & effective), and later, Phased Polaron Beams (under physics 2)(expensive, but very powerful, & penetrates normal shields)
Point defence is very important, since missiles are so popular early on. PPBs are probably the #2 most efficient weapon in the game.
For race design, I suggest taking +20 or +25 defensiveness. If the enemy can't hit you, you don't get hurt

With Point defence, they can't hit you with missiles OR beams

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If you do take god-like defenciveness, use Shield regenerators when you get to S.R. 3 or 4. Beware the SR5, since it is NOT as good as the SR4 in the standard datafiles

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With shield regenerators, & the elite racial dodging ability, any shield hits you do take will heal up before they enemy can hurt you again

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