Weavile being banned surprises me a lot, since it's not significantly more potent than last generation. Knock Off sucks, but it's still frail and it still has almost hard counters in defensive pokemon that can take a +2 hit. Mega Aggron laughed all day, most bulky waters still fared well enough.
Although I love to use it and it's my coveted stallbreaker, I think Kyurem should have been banned, since it's nearly as potent as Kyurem-B. It lacks the ability to smash things with physical attacks without investment, but a set of Outrage / Draco Meteor / Ice Beam / Earth Power is very effective at breaking physical and special walls. It's much more manageable in comparison to the unadulterated brokenness that was Kyurem-B, but it's still got great coverage, huge power from both sides of the spectrum, and ridiculous bulk with a decent typing.
But I'm happy with the other 4 bans, since, even if a few of them could be dealt with, they made the metagame less fun. With the megas remaining, I expect Blastoise, Aggron, and Absol to take up most of the usage.