KVL loop current direction convention--should be same in all loops?
No, they don't have to be in the same direction.  You just need to remember which direction you assumed because your final answer will tell you if the current is in the same direction as your assumed direction.  If you solve for current and you get a positive answer, it means your assumed current is in the same direction as the actual current.  If you solve for current and you get a negative answer, it means the actual current is in the opposite direction from what you assumed.