are stronger picks. Stacking mages can get off a lot of damage if everyone applies a stack. They also often have chained hard CC to prevent bruisers from gap closing. It's more those champs that are top tier, since the two duo lanes end up absolutely crushing due to their synergy and range. End game bruisers can get MR and try to survive, but often, 5x of a stacking champ doesn't mean just 5x the damage, it means like 7 or 8x e.g. Velkoz's true damage, Brand AOE, Lux/Syndra ult.
When I played on PBE, about 1/3 of the games were Brand, and it was always just people getting picked off and chain stunned or the entire team dying to a combo ult. Never saw a Fiora or Mordekaiser game, though they seem potentially strong and I saw them banned sometimes. Darius was often banned, as was Gangplank. Garen was annoying, but we won out in the end. Katarina I've never seen either.
Kindred sort of sucks cause no one plays Kindred yet. So you get 2-3 players just feeding. Her ult is pretty hard to coordinate too. Vayne suffers from the 5 ADC issue, you get 2 useless ones; never saw her though. Yasuo is just okay, as is Wukong. Lost a game as Trynd, might be okay, but not top tier. You just get CC'd a lot and die, plus people build armor and group up.