Sure, getting access to your spell for a turn isnt as good as returning it to your hand, but Scholar is also a red card, which means it can be played in the likes of Kuldotha Burn
Hour of Devastation revolved around the planeswalker Nicol Bolass plot to use Amonkhet for his own nefarious purposes, and so the second set serves to mostly tear down and destroy what was established in the first set
The set focuses on the Clone Wars era of the saga, so expect to see the likes of Ahsoka Tano and Anakin Skywalker as well as villains General Grievous and Darth Maul.
It never went into game play
Some cards are easier to cast when your graveyard is full, like Tolarian Terror, while others are stronger when you force your opponents to discard, mill, or otherwise fill their own graveyard