Leona wears high heels, so I automatically disregard her art design as "garbage tier".
A bit petty.
Give me one good and logical reason to wear high heels in plate mail*. The only thing it accomplishes for a warrior is arbitrarily reducing their balance and making it easier to knock them over. Someone like LeBlanc can get away with it because she's a wizard. But it's ludicrous to think that Leona's high heels aid her in blocking blows and leveraging for attacks, just as it is ridiculous to think that Vayne has not broken her ankles from tumbling in high heels. As silly as I think some of Riot's visual design is, I'm glad whomever had the fetish for irresponsible footwear has reeled it in a bit.
*Besides the rollerblade theory, which I think we can all agree is quite silly.
Boob plates can give you a concussion just by tripping on top of it.
Well, if a boob plate was on the ground and you tripped over it, you could definitely get a concussion. And if you tripped over something else and smashed your head into a boob plate that just happened to be where your head landed, that could also give you a concussion. Although the same thing could be said of a wide variety of items, so that information is not very useful to discussion.
Wearing a boobplate, tripping, and landing on it won't give you a concussion. It can break a rib or crack your sternum, both of which can be quite serious in their own right, but they aren't concussions.