It would be useful if you could specify that a Vendor is both a Vendor and Client as there are situations where you will have a Vendor who is just a supplier and you dont want them appearing in your list of clients but you then have situations where you have a Vendor who is also a Client and you do want them to appear in your Client lists.
As it stands today you can only choose to display all or no Vendors in your client lists which is not great as it will mean that I have to turn on to show Vendors in my client lists and as I add more Vendors this will make the client lists very long.