Hi creativeone,
Your question gave me an idea: A shipping quotes discount setting.

Is there any demand for that sort of thing? It could be based on the order size. Eg: x% of the orders products price.

I could set a 5% shipping discount on the orders. On an order with $100 worth of product if the shipping quotes are under $5 then shipping becomes free automatically.
This would allow the customer to have discounted access to expensive services like GXG, etc.

Is there demand for that sort of thing? I don't think it would be hard to implement on my end in the USPS module. I'm ultimately planning to overhaul the core shipping class and embed this functionality into the core. That way all shipping modules get this functionality from centralised settings.