This is probably obvious to any of you who've played or DMed Keep on the Borderlands a lot, but I wanted to see how many humanoids are in the Caves of Chaos and what types. So here is a crude treemap of the number of combatants (including females where they fight and those badass baby bugbears):
As you would expect, there is a general trend of fewer combatants the tougher they are, but hobgoblins are sort of an anomaly. And here is the map of the caves color coded by humanoid type. You can see higher up and farther into the ravine means more danger for the party:
As far as the factions go, it is almost a cross-ravine war going on; goblins and hobgoblins versus orcs. Except the gnolls sometimes ally with the orcs. The ogre generally fights for the goblins but will go to the highest bidder. Kobolds try to stay out of the line of fire. Bugbears pick off any stragglers. And the simulationist in me wonders what the hell they all eat.