Heroes is pretty damned good, but could have been so much better, if only the setups in Season 1 had been paid off much sooner, i.e., if the series had less padding.
Season 3 pays off so many of the Season 1 setups so well. It shows how great Heroes would have been without the running in place in between.
It's a dilemma for TV writers. To tell a great story they must payoff what they setup, without undue delay. But if they payoff what they setup as swiftly as they do in a feature film or TV miniseries, they run out of story too soon.
On the other hand, if they stretch the material too thin, in an effort to make it go farther, the momentum may be lost, viewers may be alienated, and the series may be cancelled.