I am very agree with you on this. It's pretty tough to up climb SOLO MMR when there are alot of tards want to play carries.
It pissed me real off, when you see there are four carries in your team when I am the last one to pick.

I think emphasize certain heroes like Lich, DP, Zeus, Necro can really bring early gank-ing and push advantage to the game. Just own the opponent real hard and it snowball.