3.0 is the VERY FIRST time we could do L51-60 content. If you expected more for endgame, you have unrealistic expectations. Still, 2x Extreme, Alex NM, Alex Savage, Fractal/Neverreap isn't terrible. During level cap increase patches (ie, expansion releases) you should expect most content to be during the leveling, not after. That comes later. This is essentially the only time they could realistically add L51-59 content so it makes sense the focus was there for 3.0. Expansions are for leveling, patches are for endgame.