one criteria to follow margin by product

Hello,
It should be a good feature to add one criteria in sale order line to follow line by line (product by product) all sales and purchases stages and obtain margin.
This feature is different about analytic line and it's very useful for several business. This feature should be like another field in all the commercial documents lines with an automatic analytic account with constraint to be unique.

In France, we call this feature "contremarque".
Goals :
1 - follow and guess at all stages the origin of the line
2 - calculate margin exactly
3 - obtain dashboard with all the "contremarque" management

Please tell me if i missed an extra addon or parameters to do this with an existant addon
Thanks