It's so important that the graph is viewed in context. As Pelion said, these EV calculations are simply a hot/cold comparison of starting hands. Hands that are -EV on the graph can become +EV dependent upon a multitude of different variables. Similarly, the vast majority of the hands listed as +EV are going to show a negative expectation when facing a raise.

Again, as Pelion already alluded to, aside from the top few hands, the majority of starting hands run fairly close. The important thing for beginners to get from this graph is the importance of playing tight. I'm not trying to belittle your effort, but beyond illustrating the importance of tight play, the graph doesn't say anything. In practice, this graph is going to vary from player to player and to situation to situation. A highly skilled player is going to be able to play more hands profitably than this graph predicts. In comparison, the graph of a poor player is going to be shifted to the left.