So who's claiming space, guarding 10' x 10' rooms with a treasure chest, wandering by at all the wrong times and generally providing opposition and occasional ally down in the big dungeon?
Kobolds- everyone's standby whipping boys. Gotta love-em even if they've been played to death.
I'm going with little para-mammal "dog headed" men for appearance and general cannon fodder and nuisance over the tuckerized trapmasters that some love to spring on PC's. They're part of the bad boy culture but for biological and cultural reasons they are a little bit apart from the host of other evil humanoids.
Goblins- keeping these little buggers but I'm going to magic them up a bit and make them the clever brewers, concotionists and even alchemists. The average goblin will be classical cannon fodder but a lot of goblins are also not all that common.
Men, Brigands/Bandits- Bad men who want to kill you and take your stuff, or just simply take your stuff if poking you in the guts and running off with your loot before you die will work out.
They aren't going to go too deep into the BigDungeon but they'll sure be a nuisance near the entrances.
Gnomes- Cute little guys. Hoe could they be a problem in the BigDungeon. A possible source of help, allies and misdirection.
Orcs-Everyone's favorite green bad asses, except of course they aren't green in the BigDungeon. Their skin tones are similar to those of men but somehow darker and more corrupt. White orcs are ashen faced albinos, black orcs are the color of sooty coal, brown orcs are the color of unhealthy mud and so on. They are not the hulking orcs of video game fame but the wiry goblinmen of evil and bestial visage.
Men, Berserkers- These bear-shirts are demented battle craving cultists. Their crazed and debauched rituals drive them into a frenzy that sends them out to seek battle and blood to glorify The Beardog.
Hobgoblins- strong-arm militant cousins of the more diminutive goblins. Hobgoblins don't have the knack for brewing that their cousins do but are known to imbibe great quantities whenever possible. Hobgoblins have a penchant for dancing in great circles and riotous mobs that look like a fight to outsiders.
Dwarf- Dvarg- nasty, greedy magical miners and crafters, not the scottish-norse stereotypes of popular dwarfdom. Friends to few but a possible source of magics and advice if the price can be paid and one can avoid being enslaved to work in their mines.
Bogles- skinny hyperactive cousins of goblins and bugbears. They enjoy pranking and thieving a bit more then murder. Bogles can move between spaces and can seemingly pop out of nowhere with a grimace and screech that can startle even doughty warriors.
Nekbet (Vulture Folk) nasty avian men that dwell in deep crags and vast caverns. They are privy to ancient magical secrets.
Morlocks - seemingly degenerate race of subterranean dwelling men with a surprising knowledge and aptitude with mechanical devices. They can sometimes be found among orcs or seeking the wares of goblins and will employ others when their diet permits.