Given corruption in the Church, wouldn't it be better not to concentrate authority in one person?

No, Jason, one person is exactly what you need. If you spread the authority out among the bishops and give them equal power with the pope, all you will get is endless arguments. You need one man who, when he is moved by the Holy Spirit, gives the definitive teaching; when he is not so moved and merely offers an opinion, then we can debate it, but you need one to hold that office. This is what stopped every argument that ever surfaced in theology; read Denzinger and see how heresies from various groups, like the one hundred seventeen errors of the Armenians, were each condemned because one man with authority acted. The pattern is Acts 15: the whole Church argued over whether to circumcise the Gentiles with no resolution until Peter stood up and declared that circumcision, like the rest of the Mosaic law, was a burden from which Christ set us free, so that we obey out of love, not compulsion. Without a pope to confirm or reject such a decision, they would still be arguing, as the Orthodox do. It is bad when we get a pope who makes poor decisions and floats trial balloons without his full authority, but you do not abolish the papacy for that; no system on earth is perfect until Christ reigns in the new heaven and new earth.