If you guys see a Desert Town Ambassador arrive at your base, CATCH HIM. The passives don't matter, as you just want him for his actual value.
>Crude Oil
>Mind Control Meds
>Homeward Thundercloud
>Remedies (permanent stat upgrades)
>High Quality Cloth
>Various valuable items to vendor (Diamonds, Precious Plumes, etc)
And probably more. Dude gives you an item every time you talk to him when he's in your base. Slap Nocturnal on him and force him to man a mounted machine gun somewhere, and you can just get free items like crazy.