I have had a thought about the VPN @freydrew
A standalone product is fine BUT the WSA Complete will no longer be Complete will it.
So why not keep it as a standalone product which can be purchased by anyone but include it in the WSA Complete package to keep the Complete name. To compensate a user could have either the Back up and Sync OR the VPN (although I would get rid of the back up and sync).
I have a feeling that this would be quite a draw for some customers to upgrade or try WSA for the first time.
Maybe worth thinking of.