I won't go hunting for the forum topics on the in-game portraits, but there has already been lots of discussion on it. Basically the agreement is that they will never change minimap icons or kill callouts, since they all have to look unique and discernible, and while the portraits would be a nice touch, they would have to make a portrait for every skin (easily 300+ skins in this game now) and it would be a lot of work for minimal gain
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