Never played the listed classes, but we did do an "Average Joe" game where everyone played run-of-the-mill peasants with no special abilities. All were human and the plot revolved around recovering some pigs that had been stolen by the village swineherd, who had in turn sold them to a bunch of hungry goblins. The goblins were passing through to a new lair and didn't have the strength to risk fighting the villagers, but they did have gold to pay the swineherd. To make things really fun, the fight wound up taking place in a very slippery, muddy field. I think we made more DEX rolls than attack rolls!
Anyway, it was a fun one-shot deal and we called it "We Have No Class When Gaming With Pigs".