Customer Discounts....

Is there a simple way to establish a customer percentage discount?  For example Customer 12345 XYZ is set to get a 10% discount on all orders which pops in automatically whenever the customer orders

We are aware of the following:
1.  Price Level Discounts
2. Promotional Discounts

Number one is cumbersome but can be deployed if necessary(that is what we used to do)

Number two requires the customer and the sales rep to remember it every time. There appears to be no way to set a customer based default promotional discount.

Ideally this is the situation that we would want to happen:

Customer 12345 XYZ has a 5% discount with a single order between $X amount and $X amount and a 10% discount with a single order between $X and $X, these would kick in on the sales order automatically with no entry other than the items for the sales rep to enter.