Vendor-specific item details: a wish list

I just filed an ER with support with the following text.  Feel free to add to the list and I will update the case.  Keep in mind these aren't "Inventory enhancements" but enhancements to defining item details per vendor.

My case content:

On an item record we have the sublist at the bottom where we can enter a vendor, part number, price, schedule, etc.

We need more.  Here is a list of fields we need to define per vendor:

1.  Item weight - I may sell "5 pack of rags" but I may purchase rags from 10 vendors.  There is a good chance the won't all weigh the same so I need to set this somewhere so shipping (purchase) can be determined.