I don't know. On one hand, I agree with you, it will probably attract those players who did one or two runs and then stopped. It will also let us test a lot of new features, since lv5 is full of them for every single class if I remember correctly.
On the other hand, I think they need to focus on the most "controversial" aspect of the game, so to find a good middle ground on top of which add more meat to the grill. Not to mention that, without more content, level 5 will come too late in the EA to fully experience it or it will trivialize a lot of the fights if it comes too early.
