When i first played the dreadlords campaign, i wondered this too?
This is what i recommend - build nothing for them to kil! simple! then protect your planets from transports with cargo hulls loaded with engines, sensors and 1 little weapon. They are fast enough to evade all Dreadlord combat ships while they are at it. That works good while you research better techs but.... eventually the Dreadlords will fleet up a transport with an escort combat ship, then your cargo hulls cannot stop them taking your planets!!. But by then you should be able to build fleets of tiny hulled ships powerful enough to kill Dreadlord ships. You will probably find it necissary to have some reasonable engine speed on your tiny hulled ships otherwise the Dreadlord ships will be able to pick them off before they can fleet up.
Remember the power of fleets.... this is how you will defeat the Dreadlords.
Edit: Oh i forgot to mention.... don't bother trying to use any defences on your ships, it is a waste of time. The enemy firepower is so strong that defences and hitpoints are irrelevant. This is why i recomended using tiny hulled ships.... each weapon on the Dreadlord ship will be limited to the hitpoints of each tiny hull! So if a Dreadlord weapon is capable of doing 100 points of damage, and your tiny hull has just 6 hit points, well then all that extra power is lost for them. In earlier versions this strategy was even more valuable, because ALL weapons on the Dreadlord ship fired at the one Tiny hull per round, but this was later fixed so it is now each individual weapon, but still, a good strategy using Tiny hulls.
