I've been NPC'ing a lot lately, low enough rank I don't get flamehawks; but almost as bad are the Stryll Assassins. They are common, so they appear quite often; but they have almost twice the hull of any other common and combat skills better than many uncommons. They drop Dark Badges, but this reward doesn't compensate how tough and common these are.

It seems to me that Assassins may have been intended to be an Uncommon NPC, rather than Common. The other NPC that I know of that drops Dark Badges, the RSL Siege Cannon, is weaker yet is Uncommon.

THey're to stop people ranking very fast off of NPC's.

deal with them, get better attack and defense and it gets easier
dark badges, once you get enough, are actually very useful.