My Kobolds hadn't bit anyone until recently and was wondering about this myself. I had thought that perhaps the sieging Orcs intentionally caused a forest fire. I'm certainly finding the Kobolds to be full of fun!
Losing 15 Kobolds every ambush of Pandashi that don't trigger the 30 traps I set up and actually can beat Ogres is fun! The best part is a week later and we are back to full strength with child legendary hunters. Even though they rarely return with kills before their blowguns run out of 25 darts, as nothing dies from getting hit by the equivalent of 25 pin pricks.
The only hitch seems that the Kobolds rely rather heavily on wood for fuel and Woodstalks are not particularly ideal for farming for a couple of reasons. The first being they are above ground and I want my little people to be hiding in caves for the most part. The more impart aspect is that it's not highly efficient. I like the idea of using peat as some kind of fuel, since my Kilns often run out of charcoal when there is no more wood.
I really enjoy attempting to use Ogres constantly to fend off ambushes and sieges. Except they almost always end up running away from some fights if not leashed to the door and I like them to be free! I always try to equip with them with trees, but my last Ogre was dual wielding some silk quivers, I'm not sure if there is a conflict there or if the tree-equip just upgrades their damage. I have yet to be able to see it in their Inventories.
Regarding trap spiders, do they have to be positioned by traps as an attack is occurring in order web enemies? I am assuming they can't be pre-webbed so my spiders.
Just my random ramblings, but overall I really found this to be an extraordinarily fun mod.