Personally, I like the more mystical and contemplative writings of Plato in and of themselves, but I think that Aristotle's metaphysics may well be better suited to Catholic theology than Plato's, because in the Church we are more interested in the individual substances than in the idea, e.g. we love one and other's souls, and not just the general idea of a soul. I think that the Platonic idealism would undermine the reality of the Incarnation and of Transubstantiation somewhat. I may be wrong, but it would seem to me that Plato would see the Incarnation and Transubstantiation in the Blessed Sacrament as abominations, because the World of Ideas is always superior to the world of matter and so for God to manifest Himself like that in the material world would be a theological disaster for Plato. In Plato, the body of Our Lord doesn't have existence so much as the transcendent Idea of it, which is somewhat echoed in the teachings of the Gnostics who said that Christ was a divine spirit, and His "body" was not really His, and that when His body was crucified it was not really Him. Aristotle wouldn't seem to have this problem though, because he admits the reality of the substance of the body. For Plato, the soul's existence in the body was a kind of mistake or punishment, and salvation was to return to the world of forms, bodiless. But we believe that God made us good, and that we are to be resurrected in our bodies.