I like Kobolds, they are small, craven, puny and devious creatures, but, they are also the absolute masters of the art of traps, and while I could throw a small army of these creatures, in basically any configuration, at my current party of six level 13 adventurers.. the outcome would always be a large pile of very dead Kobolds.
But of course, that is without the traps being in the scenario.

Now here comes the cunning plan.

The Dwarven Paladin character, Cobalt (corrected spelling of the name this time), has been given a divine mission by his God Erathis, one of the bits of the mission is to find the individual called Fistenfoe... The player doesn't know it yet, but Fistenfoe is actually the most ingenious Kobold Artificer that has ever lived (hell, he has eight levels in the artificer class!).
Unfortunately, getting involved with Fistenfoe means getting caught in the middle of a war between two rival Kobold tribes, one of which is in service to a powerful dragon.
While Fistenfoe is an unbelievably skilled maker of traps and devices, his opponents are tactically brilliant, and highly skilled at the capturing, breeding and training of pests, oozes, horrors and assorted gibbering nasties, which they use to great effect.
The details I have yet to work out, but there is plenty of material on Kobolds that has been released for 4th edition already.
I just have to come up with some truly diabolical traps and some rather interesting variations on vermin, oozes and constructs for later deployment.

Should be fun!