Is there a working way to override product and still have custom field pricing

[bunglehaze]

Just a quick note as I am struggling to see a logical way to do this.

I offer a product at say £15.99, but for the time being I want to override this down to £13.99 to put it on sale - not using the calculation system, as a product by product basis.
I also offer upgrades on the standard item - lets say I have in custom fields:

colour > black (no additional charge)> silver (no additional charge)
type > powerful +£1 > extra powerful +£2

What is happening is that the override price is overriding ALL prices and not just calculating the product itself, therefore if a customer wants to purchase the reduced price item at £13.99 and then selects the upgrade option the overridden price remains at £13.99 which seems flawed to me.

I know I CAN create a calculation rule for each item required but it is a bit of a mess around to do so when the override is ideal in this situation. Is there a way to add into the override section another checkbox that says base product/no custom fields which ONLY sets the reduced price to the base product and NOT that of the fields?