Actually,
It seems like the accidental presses, to you, are unavoidable (although in my experience and in those of my peers who own iPhones, we believe there's nothing wrong with the Favorites or Recents)...
In order to keep your accidental presses from actually making the calls, just maneuver those menus keeping your fingers to the right side of the screen. In both menus, tapping a name directly initiates the call... but if you keep to the right, your taps will initiate secondary menus. Just watch where your fingers land, and the "Confirm" feature is not necessary.
+Here's an example: In my Favorites, each of my contacts there has an accompanied label called "mobile" and a blue arrow. I scroll and select names keeping my fingers to the right, so if you make an "accident", no worries, the iPhone just responds by taking you to a secondary menu like the Contact Info for that particular contact. Hope this makes sense.+
But if you +*really really really really really really*+ feel like this is something all of us _absolutely positively_ need anyway, then just send your thoughts to Apple directly:
http://www.apple.com/feedback/iphone.html