Allowing 6 Exp as opposed to 5 exp does not greatly unbalance the monster. In fact allowing them student of the temple is mostly just flavoring and makes them only slightly more dangerous than skeletons.
The monster creation rules are fairly good except for the odd 1 exp worth of loot or power. Generally speaking if there is only an extra exp, I would just keep the CR at the lower level. If you end up 1 or 2 exp or yen short of the next CR, I would just add another modifier or weapon.