one thing i found very nice for such type of script events was those used in neverwinter nights

in fact, every monster have some different type of events pre defined ( death, see something, on spawn etc ... ) and there was a default script for each of these events but they were not used except the onspawn one

in the onspawn script if we put this line :
SetSpawnInCondition (NW_FLAG_DEATH_EVENT);
then the ondeath script was fired when the monster died^

i don't know if it can help but it was a smart way to use such specific scripts of monsters