Damage taken is a poor stat
Tracking the damage taken by each champion isn't a very good stat to track. Sure, you can tell how badly someone was with this but I don't think that is particularly useful information. It seems to play the role of showing who performed poorly where as the other statistics at the end game screen show how well someone is performing. Damage taken seems like a fairly poor statistic, but perhaps I am missing something important about what it provide, i welcome insight if someone has that.
Until then I think a simple shift to Damage absorbed would be ideal. This could work in two ways. Either damage absorbed by shields throughout the game or the damage prevented by defenses. With the shields, it would be a good tool to see how effective a support's shields are being. With the damage prevented it lets us know how effective a tank we are. I think it would be more useful information to see that the tank has mitigated 20,000 damage through good positioning and tanking then to see he took 10,000 damage just like everyone else on his team.