This is already implemented and, if I’m not wrong, called ‘virus targeting’.
This is transparent in the Professional version (there is a setting for that).

Other questions:
Disable automatically contacting updates server: see ‘settings’ link bellow in my signature or just configure it to ‘Manual’ (settings > Updated (Basic)).
Customize heuristics. Go to the provider settings (Internet Mail and Outlook/Exchange) and configure it :wink: (you have to choose ‘Custom’ level of protection).