The idea behind would be try and kill the least amount of enemies possible, if death couldn't be avoided it would have to occur the least violent way as possible. So no Destruction magic or Conjuration, Restoration would be the main magic school (and yes it is a valid school) supported with Illusion and Alteration. Wards and barriers along with fear and calm spells to battle enemies and Frenzy as a last resort. Alchemy will be just as important, using it for restore and fortify potions, no damage potions. No slaying of any animals, even hostile one and no wearing of any furs. Enchanting can only be used for boosting stats, no destruction. If you RP then no cooking with meats, just vegetables.
It would be a challenge to play the game in this way, and I may explore it soon.
Good idea or bad idea?