Please add Per Item Price Adjustment to UPS Shipping Plugin

Currently you can only enter a Price Adjustment per Service level for the entire cart.

In addition to that, I would like to be able to enter a Price Adjustment Per Item for each Service level.

Existing functionality:
10 items in cart
Price Adjustment: $10
Calculated shipping: $5
Total shipping price: $10 + $5 = $15

Suggested Functionality:
10 items in cart
Price Adjustment: $10
Price Adjustment Per Item: $2
Calculated shipping: $5
Total shipping price: $10 + $5 + ($2 x 10 items) = $35