I usually have hard time seeing boob plate armor as aesthetically pleasing though especially if it's boob cups, usually it's opposite and armor would look better without boob plate. I think majority of boob plate armors are just included in the games cause it's how female characters have been done years and developers can't figure out new ways to do armor for female characters so they just take male armor and stick boobs on it or invent armor completely by making it bikini armor 
What I have observed at least for me better way to show of that character is female with armor is to make armor more female form fitting:





Note that all armors show that characters have boobs, but they don't have boob cups. Some of these are bit more realistical than others, but I think their fitting to game depends on art style.
What I don't think looks good:


Though not all boob cups are bad looking, but I think majority of them are and they are just easy way for developers to made female armor without having to design much and think different approaches.