One thing that has been kind of annoying me recently is that when a unit upgrades it losses its kill count. I personally would really like it to keep that so I can see how many Ive really killed at the end of a game

Another thing thats loosely related is that some units such as SAMs, NGs and a couple others dont display ANY kills at all, even if never upgraded. Not sure if thats a me problem or not, I play on PC.