Starcraft II Analysis - Why Siege Tanks are Currently Overpowered

I strongly believe Siege Tanks are overpowered, currently. the 60 to 50 damage reduction wasn't enough. As
- Siege Tanks can come out pretty early, earlier than a Hydralisk
- On paper, its AOE dps isn't that much, however, it is able to kill many units before it can reach it
- Due to the new Starcraft 2 AI, it rarily rarily splashes friendly units, which was a big weakness of Siege Tanks in Starcraft 1

In conclusion, I think it needs to be nerfed, have its gas cost increase or minimum range increased or something else