I would like to request some bolstering of the "Sales Person" feature. I understand Zoho added Sales Person to the invoice and estimate documents, which is great. Here are some improvements I think can be made to the Sales Person field:

(1) Integrate it with the "staff" role of the Users preference pane. If I invite users to join my books.zoho.com organization, then it is a fair assumption that at least some of them will be my sales people. I would like the Sales Person box to populate from that list [but don't lose the ability to type in for those random events as well].
(2) More than one Sales Person. Not all projects can be managed by one person. Plus I could get some reports on how often certain people work together and whether that is profitable or not. Seems handy.
(3) I would like the ability to email the estimates and invoices documents to the selected Sales Person(s). Currently the workaround is when I email a document to the customer, I need to hand type the sales person email which adds it to the contact sheet for that customer. It would be great if I could email the sales person and not the customer [for less common instances], but at least being able to email both would be helpful. I do not think it is helpful to add the sales person as a contact to the customer's contact sheet. That is messy and inaccurate: my sales person is not a contact at my customer's organization.