Imps and Dragonlings
(Armor 3, Health 11 to 18, Damage 2-15/Spell)
They like Shock and area effect spells (like Sphere of Negation). The exception is the Rogue Imp you get from the Mages Guild. These have a couple of other spells up their sleeves (sometimes), but their tactics are the same as regular imps. After they get off their one or two spells, theyre easy to take out as long as you have Steel or better to swing at them. Treasure is usually less than 10 GP and a couple of cheapo ingredients.
(Armor 6, Health 14 to 42, Damage 5-15/Spell [Fireball])
They can supposedly heal themselves. Not bad for a baby. They swing pretty frequently. Only the Dragonlings encountered on Knights Guild Quests can be soul-trapped and used in the item maker. All others can be soul-trapped, but they won't work in the item-maker. No treasure, so pickpocket them a few times before you off them.