Perhaps I should have posted this in the hero balancing thread. I was, however, afraid that it would get lost there. My point is that the new heroes are a huge advantage not by they own but because you can combine them with the preexisting heroes. Here is a recent gameplay example.
Map: Central Sahara
PLayers: Argammon (no new heroes) vs Igor (new heroes)
Obviously, who controls the central island usually wins the game. Therefore that is where most of the fighting is going on. Both of us have a high level amazon. Igor also has a decent horselord. I basically had 2 options:
1) Attack his stack in the desert and fight against +25 horselord command.
2) Sit in my cities and fight against +20 amazon command.
I choose option 1) because I had a sandworm. The result was that I lost the fight even though I had better and more expensive units. Now tell me that the horselord amazon combination is not an advantage for paying players. The amazons weakness that i cannot defend itself on the open field basically is mitigated by the horselord.