I'm still hazy on the specifics, your explanation of how you want this to work is a little to general for me to able to give specific instructions on how to set this up.
From what you have said so far, it sounds like you want the shipping to be item specific?
you want to charge Weight * 1.05 for the first item and Weight * 0.30 for each additional item?
so if you where to order:
qty: 2 Item: Apples Weight: 5 or (5 * 1.05 = 5.25) + (5 * 0.30 = 1.5) = 6.75
qty: 3 Item: Oranges Weight: 4 or (4 * 1.05 = 4.2) + (4 * 0.30 = 1.2) + (4 * 0.30 = 1.2) = 6.60
qty: 1 Item: Grapes Weight: 3 or (3 * 1.05 = 3.15) = 3.15
the shipping total should be charged as $16.50?
Do i have that correct?