Interesting Addition to Death Screen
I find a lot of people really don't grasp how much of a impact a single death can have in a game. Players constantly make poor decisions and dont understand the consequences of their actions. I think a very good training tool for players would be to include a counter which tracks how much of a gold, exp and objective advantage the other team gets as a result of your death. This counter would be displayed on your death screen and disappear once you respawn.
Hopefully this will help players realize that a kill for a death is rarely "worth" and that dying to get a tower isn't a good idea when the enemy team can get baron and 2 towers before you respawn. Also, this would help new players understand why it's not a good idea to keep 1v1ing an enemy with a huge gold and exp advantage.