Think about it.
After listening to unused audio clips, it's proven that the St. Johns brothers planted the bear trap that grabbed David's leg. So, that means that if they HADN'T done that, we never would have heard him screaming, and we never would have met Ben.
Also, if we never met the St. Johns, Mark never would have been killed, nor Larry.
With Larry alive, Lily never would have snapped and shot Carley/Doug.
Also, Larry/Mark might have helped during the Bandit attack in episode 3 and possibly stopped duck from getting bitten.
Ben caused Carley/Doug, Katjaa, Duck, Kenny (By loss of will to live), Chuck, and Brie.
We can cross out Carley/Doug, Katjaa, Duck and Kenny, and that means that Chuck and Brie would have lived.
So, in conclusion, with all these characters alive, things might have turned out better for Lee and Clementine.