For instance, an important and (according to many Christian theologists) necessary part of the Christian heaven is being able to view the Christian Hell and enjoy the torture of the evil sinners there

Some think the opposite, such as the pastor of a church I attended as a child. Apparently there was concern about the knowledge of loved ones' suffering in Hell interfering with the ability to experience pleasure in Heaven, so he claimed in a sermon once that God must somehow "shield us" from that knowledge.