@extomar: Yeah that's a clear issue. Dota had some hero balance issues during previous tournaments, but TI4 has an amazing breadth of picks. I'm really quite impressed with it.
How Riot keeps trying to appopriate their characters to whatever is in vogue at the moment is just ridiculous though... There will never be a bigger than 30~ champ pool in pro play if they don't start to try and balance for versatile strategy instead of current meta. I kind of wish they could show off some understanding that you can give variation in the game with bigger strategic changes instead of just creating arbitrary goals like "how do we beat current OP hero X" and then create a new monster to beat once that one is figured out.
One of the interesting things about the Dota meta is that it shifts nearly every month, while there's usually only a balance patch every 8 months or so. It's due to the way Icefrog has the game balanced: heroes are all unique and viable in a very specific niche, and heroes have multiple hard counters to each other, as opposed to League where heroes are just balanced around being viable in a role (AP, ADC, Jungle, Support, etc.), seemingly due to the way they've structured their pay model. In Dota, a hero gets popular and everybody starts picking him, then people figure out what hard-counters that hero, so they start picking that, then eventually people start picking that hero a bunch, so people move to what hard-counters that, etc. The versatility of what hero lanes where, heroes being able to fill multiple roles, and heroes hard-countering other heroes is what makes the Dota draft so important and interesting.