The question is absurd: when you ask, 'If God is both all good and all powerful, why then does He allow suffering?', what you are really asking is, 'If God is both all good and all powerful, why then can He not make me (the questioner) - who is just as much a part of a universe in which there is suffering as is any other part - be at the same time the exact same questioner, but one who is now part and parcel of a universe in which there is no suffering?' Which, reduced down, is the same thing as asking, 'Why can there not be, at the same time, X and the preclusion of X?'