I have always loved the metal Orlock figures. They seem such a nice mix of guard, army, hive, scum and gang.
I actually use a fair few of them for a couple of squads (I have enough for a platoon... just need painting up and some need stripping).
They are also my chosen gang for Necromunda. I managed to get a fair few of them cheap on ebay many years back and eventually decided to paint them up for my IG army.
My IG army now has a platoon (of various sizes, but at least 3 squads) of: Catchans, Cadians, Tallarn, Orlocks, Militia, Old Style Stormtroopers.
They seem to fit the ideal of a hive platoon or even just conscripts/PDF.