I always find that when doing my steel/iron drag tasks I get LOTS of charms, irons drop all 3 at a time, and steels drop 4 at a time. Giant rock crabs are good for gold 10 at a time, and daganoths are really good also.
fire giants for golds, blk demons, dust devils, water fiends for crims, and your an idiot if you hint for greens same exp as crims but double the cost. Blues are rare cant hunt for those