The trouble with kingdoms of heaven on earth is that they're liable to come to pass, and then their fraudulence is apparent for all to see. We need a kingdom of heaven in Heaven, if only because it can't be realized.
As for evildoers, for them awaits a painful chastisement; but for those who believe, and do deeds of righteousness, they shall be admitted to gardens underneath which rivers flow, therein dwelling forever, by the leave of their Lord, their greeting therein: Peace!
When we die and go to Heaven, our Maker is not going to say, Why didn't you discover the cure for such and such? The only thing we're going to be asked at that precious moment is Why didn't you become you?
Theology: There is a heaven, for ever, day by day/ The upward longing of my soul doth tell me so./ There is a hell, I'm quite as sure; for pray,/ If there were not, where would my neighbors go? --Paul Laurence Dunbar