3 Ideas about Emails, Customers and PDF saving

I guess we all use Manager differently and have different needs… I would like this options and I have not found a way to do any of them.

Auto save invoice PDF to specific folder Year/Month/Day
Having access to Invoices with out stamps

Send Email from Sales Invoices>View>Email Add some sort of option to choose from recently used Emails or by Customer ID

Option to link Customer to Inventory Item’s? (so if a Sales Invoice is created to a specific Customer "you can choose from Inventory Items linked to that Customer only.