It seems to me you miss to understood what I was pointing to or I wasn’t able to write it in details
Current implementation we can link sales invoices to sales order by choosing sales order in sales invoice which will help us to know for every sales order what is invoiced and delivered and what is pending for delivery and invoicing.
In credit note tab there is no option to choose the sales order for every credit note which will result in showing in sales order tab sales invoices issued more that sales order value
this subject could solve my issue