I think that it’s not a so new idea but I think that Apple should implement an Add to Home function for Contacts… So You can add your favorite phone numbers to your Home screen and call in one tap…

You should also be able to choose an icon or the photo associated with the contact for the icon on the Home screen.

I know that there are workaround for this using the tel: protocol and even several free applications that only do this… call one contact of your address book but I think that a system function could be better.