I have recently attempted to employ US military doctrine to my traps (small ordinance to wound and pin down rather than large ordinance to kill). Rather than a few, big traps, I've been using traps that generally have 1 full size component (spike ball or menacing spike, generally) or three normal weapons. The reason I've done this is for maximum efficacy.
Theory:
Azum McGobboLasher steps on trap 1 (Big friggin trap): He is completely wrecked, and dies on the spot. His carcass may jam trap.
Azum McGobboSwordsman steps on trap 2 (US inspired trap): Steps on it, gets stabbed by three crap metal large daggers from dead thieves and one iron spear from last gobbo attack. (I have legendary mechanics, so my mechanisms are pretty good and as a consequence accuracy is too), Azum stumbles a few tiles, falls unconscious and is killed by Urist, or he bleeds out. His carcass does not remain in trap.
!!SCIENTIFIC!! results:Pending next gobbo siege.
I should qualify my earlier statement. When used in conjunction with cage traps, I go for trap 1, so that the wounded guy does not crawl to the next tile and set off a trap, effectively rendering the weapon trap useless as the cage trap would have gotten him anyway.
What are your thoughts?