Such a worthwhile question deserves an attempt at an answer.
The short answer is that any alternative is completely unthinkable.
I remain a Catholic
Because the Catholic Church today is the same Church begun by Jesus with His Apostles.
Because the Catholic Church has been a continuous witness to the resurrection of Jesus for almost 2000 years.
Because the Catholic Church wrote the New Testament under the inspiration of the Holy Spirit and is the 'Church of the living God, which upholds the truth and keeps it safe' 1 Tim 3:15 or as other translations say 'the pillar and bulwark of truth'.
Because the Catholic Church has preserved the faith of the Apostles and the early Church and has never watered down its teaching on abortion, contraception and marriage, unlike other churches.
Because the Catholic Church has been led by a successor of St Peter, the prime minister of Jesus, for its whole history.
Because the Catholic Church deals in reality and not in symbols. Baptism makes a person a child of God. Penance cleanses a person of sin and grants power to overcome sin. Confirmation empowers a person with the gifts of the Holy Spirit to enter into the mission of the Church. Eucharist feeds us with the true body, blood, soul and divinity of Jesus Christ, to make us one with Him and with each other. Marriage transforms the bond of love between a man and woman into a life-giving icon of the love between Jesus and His Church. Holy Orders transforms a man into a priest. The Anointing of the Sick always heals, body, mind, soul, spirit at a level chosen by God and protects a person in the final conflicts between good and evil as death approaches.
Because the Catholic Church is universal. Anywhere in the world I can walk into a Catholic Church and can participate in the Eucharist. Where ever we find ourselves, we offer the same perfect sacrifice to God that Jesus offered on the Cross.
Because the Catholic Church prays in unity. Across the whole world (apart from those places where regional feast day liturgical prayer takes precedence) members of the Catholic Church are praying the same set of psalms, canticle and intercessions at morning and evening prayer each day. The scriptures read at Mass are the same, too.
Because the Catholic Church is serious about calling Her members to holiness. She is the one surrounded by the great cloud of witnesses, Hebrews 12:1, of Saints from every age, nationality, and walk of life. We know, treasure and celebrate the great witnesses to Jesus in every century, and are encouraged to imitate their virtues. Thecla, Clement, Perpetua, Augustine, Jerome, Gregory, Basil, Benedict, Boniface, Patrick, Francis, Dominic, Catherine, Gertrude, Charles Borromeo, Ignatius, Kateri, Bernadette, Maximillian Kolbe, John XXIII and many thousands more.
Because the Catholic Church is bigger than any one of its worst members. Even if a priest is at enmity with God the sacraments he celebrates are still 100% valid and life giving.
Because the Catholic Church is the wise householder who brings out from Her storeroom things both new and old Matt 13:52. Not only does she share all that the Holy Spirit is teaching her now, but she preserves and shares all that the Holy Spirit has taught her in the past. What a vast treasure house there is of the writings of popes, Saints and Councils, of prayers, songs, meditations and scripture commentaries, of wisdom on how to live the counsels of chastity, poverty and obedience, and on how to live family and community life.
Because the Catholic Church gets persecuted, just like Jesus promised She would.
Because the Catholic Church enables its members to worship in the fullness of the truth and the fullness of the Holy Spirit. John 4:24. Safeguarded in truth by the magisterium of the Church and open to the miracles and charisms of the Holy Spirit under the pastoral care of the bishops.
Who wouldn't want to be in, and remain in, the Church that Jesus Christ founded?
That's why I remain a Catholic.