When using group customer credit limits there is no easy way to report on which company in that group has used the available credit limit

You should be able to report on the balance outstanding across all LE's for all group limits. You don't want to go into each customer and see the balance. When you have 1000's of customers this isn't feasible. You need speed

As a user I want to see the group credit limit for a customer, I would then like to see by LE the balance that each one has used