Dirty little secret from 1st edition: Monsters were AC, HP, and Dmg..that was about it. And yet, somehow, different AC/HP/DMG seemed different. Good DMing, I suppose, prompted with the barest fluff in a MM.
I too would appreciate a list of traps for Kobolds, e.g. (since that is how they presented them) but perhaps that is covered in the DMG and if so, I appreciate not wasting space on traps that could be used for more monsters.
In regards to things like traps...I am torn. Publishing them certainly helps in that I don't have to think about it, and it would stimulate me to emulate with my own creative designs, but there are downsides: You might get into the same rules-lawyer minutia arguments you find in Char-Op threads, players will want to take and use the same stuff, so designers have to be extra cautious and careful, and last but not least, it makes it easier for me to cop out and just use whats presented instead of being creative.
I think, in general, the player base knows kobolds well enough without a lot of fiddly bits presented. DMs, for the most part, can and will fill in the blanks. For new DMs, an adventure presenting them with all their "Tucker Kobold" glory, would go along way to enrich the MM.
For now, I think it is an opportunity to create content and post it here for free on ENWORLD. What do you say? Make this thread constructive, instead of merely critical?
Kobold Trap: Moulin Rouge (Red Mill)
The Kobolds collect bits of iron and grind them own into filings (dust) which they store in a bellows sealed with a tiny plug of wax. They position this bellows such that when a creatures activates a trip wire, the bellows blows iron filings all over a 10' cube (DC 13 Perception to notice. DC 10 to deactivate). These filings stick to hair, clothes, etc. and can not be removed except by a thorough washing or Prestidigitation/Thaumaturgy spell. They typically position many of these bellows in areas where Rust Monsters have been gathered. Increase frequency of wandering monsters rolls. If a wandering monster is rolled, use a Rust Monster. Rust Monsters always attack those covered with filings and possessing metal weapons and armor, over those without filings and possessing metal weapons and armor. Tribes of kobolds who use this trap can be spotted by their curious lack of iron weapons and armor.