Michael Horton’s Does Calvinism Make God a “Moral Monster”? is intriguing and important. He concludes:
Any view that makes God the author of sin does indeed turn the object of our worship into a moral monster. However, any deity who merely stands around reluctantly permitting horrible things for which he has no greater purpose in view, is equally reprehensible. In the one, God is sovereign but not good; in the latter, God is neither. Once you acknowledge that God foreknows a sinful act and chooses to allow it (however reluctantly) when he could have chosen not to, the only consolation is that God never would have allowed it unless he had already determined why he would permit it and how he has decided to overcome it for his glory and our good. Mercifully, Scripture does reveal that God does exactly that….
Reformed theology has maintained consistently that Scripture teaches God’s exhaustive sovereignty and human responsibility. God does not cause evil. In fact, God does not force anyone to do anything against his or her will. And yet, nothing lies outside of the wise, loving, good, and just plan “of him who works all things after the council of his own will” (Eph 1:11). That God’s sovereignty and human responsibility are true, no serious student of Scripture can deny. How they can be true is beyond our capacity to understand. As Calvin put the matter, following Luther, any attempt to unravel the mystery of predestination and human responsibilty beyond Scripture is a “seeking outside the way.” “Better to limp along this path,” says Calvin, “than to rush with all speed outside of it.”
This answer may not satisfy fully the philosophical mind nor scale the depths of theology, but I find it hard to disagree given the witness of Scripture.