Still fairly new to the game, but I was playing the Zoltan ship and got the Glaive & Weapon Pre-Igniter combo in sector 2 last night...wow! I don't think I took any damage until sector 5. I didn't even worry about defensive upgrades until sector 5. For sectors 5 through 7 I added a 3 shot laser to weaken the shields a bit, and used the 4 second recharge ion weapon and a bomb for the boss. (I did push the shields to 3 and engines to 6 in the latter sectors just in case)
This was my easiest run through yet. Since I took almost no damage the first 5 sectors, I had plenty of scrap for upgrades and augmentations.
Now to start another game and get pummeled again...
