That post was 2 months ago. Yes, now I've played the DL campaign, but not completed it yet. And I knew that before I read you post(which was just now), so no spoiler here.

I've come upto the "Apocalypse" mission in the DL with no mission lost yet on Painful but moved upto Crippling recently.

One thing I've learned is that you don't have to match the Dread Lord firepower or to level your defences against their attack. I can get to Advanced Miniaturization, Medium hulls, Phasor V, Enhanced Logistics, Warp Drive, etc by mid year 1 and the Dread lords had about 60 operational ships by that time while my ships produced about 33 attack. Believe it or not, I've killed 32 dread lord ships(frigates, defenders, escorts, fighters, etc) while losing 4 frigates myself.

The secret is to get first strike. The Dread Lords use little(compared to their attack rating) to no defences and they have the same ammount of HP as you. All you have to do is to strike first(and have Micro repair bots and Xinathium Hull Plating) and eliminate their HP. Have above atleast 22 attack on your ships and strike first. Thats all you need.

That's DL of course. Playing through DA, if you try this, your ship will get killed an their ship will survive with 1 hp. In DA, fleets of super-defensive ships would be better since the Dreads generally don't use fleets and defenses.