Every time I play sandbox I beeline missile tech. Why? Because the defender (small missile ship) has twice the fire power of its beam and rail equivalents. Hell, it has more firepower than the medium ships-the corvette does 8 points of damage and the defender (with basic missiles) does 12. I'm playing a normal came right now where I haven't built any medium ships (my first few large ships are entering service now and guess what weapons they have) just huge swarms of defenders (think 13 ships per fleet) that destroy pretty much everything and I have a huge lead on the other factions (strangely they're building the same harpoon boats I am but their fleets are smaller.)