xin zhao has more utility than gangplank, no global but he has far more disable.
Riven bot is a specific counter to some champions bot. Maokai and jarvan should be included though in the bot champions.
Poppy is kind of outdated, she is much squishier than people always complain, and easily dealt with at high ELO by focus fire and co-ordination. She's still decent, but I think she's much more of an AD champion, and even then a rather average one. I'd appreciate some reasoning behind putting her higher as an AP burst, because she falls under fizz easily in my books.
Taric outplays zilean as support. He has a stun, armour aura, dmg from ult, - armour proc, and to finish it off a heal. He is definitely a great support for certain AD carries
Sejuani is a good disruptor, she can keep people disabled for a long time, very solid disruption. She isn't quite into top because she deals very little damage. Malphite on the other hand has too long a cooldown, and is only good at countering physical dps champions. A -AS AoE doesn't really concern most champs, and his knockup ult is on a huge cooldown too, while his q is just a meagre slow