Indeed. The Wheel creates ta'veren and spits out Heroes and so forth as a part of a self-correcting machenism, but the battles they live are not part of the primrary weave of the Age Lace, merely a way of getting back in line after the Dark Ones tampering. If the Dark One ceased to exist than the wheel would stop sending out Heroes and so forth without pausing for breath--including the Dragon. They are tools to a point, not requirements of the Ages.

Not entirely, Luckers.

 

The Heroes are also used to shape history to the Wheel's liking- when it needs great upheaval (say, to end an Age), or when the cumulative effect of free will has created a drift.

 

RJ confirmed there are non-Dragon incarnations of the Dragon soul. He's also said the Wheel uses ta'veren and Heroes to oppose each other on occasion. From this we can conclude the obvious conclusion from the set used anyway, that the Heroes are the key figures in history, and are the source the Wheel calls upon to do battle with the DO when needed, since they are its most effective and efficacious tools.

Ta'veren are more of an advantage than the horn, I would think, since its said to be something the Pattern uses to correct itself