1) Imoen is restricted to detecting and disarming traps as a thief. Lockpicking only if we need to get to some kind of villain or required to advance the story. No pickpocketing at all.
2) No picking up items off 'innocent' NPC corpses, from people's houses/world objects.
3) All excess money goes to temples (I wish Paladins got additional reward refusal dialogue options >.<).
4) No pre-buffing before a fight unless my character would see it coming. Also, only Imoen can go ahead and scout (no setting up a mage to get a fireball in at the start of a fight to pull enemies)
5) Not using any 'spoiler' items (hidden objects in area maps)
Any others that come to mind?
Edit: So sorry about the multiple posts! I kept getting a technical error but I guess it was still posting :/