Everything about yorick is dumb and he needs a complete rework
1)ridiculous damage with no damage items 2)ridiculous tankiness with no tank items 3)ridiculously long cc with low cooldown 4)melts towers with no damage items
just about the only thing yorick doesn't have is a pussy shield block or dodge like riot gives to everyone else that's broken(not that he needs it). seriously this guy is stupid from lvl 1 to lvl 18.
and
Second point, he's too tanky, well, again, name one of those champions that aren't tanky.
Thirdly, long cc. His cc consists of a slow, and a wall, none of these are hard cc and don't really impact his laning too much. e isn't strong for the slow, its strong for the speedup and aggro on ghouls.
Lastly, melting towers. Yes, he does. He's REALLY good at it. Why shouldn't he be? Some champions deserve power for drawbacks