From the grammatical point of view, the phrase "this rock" must relate back to the closest noun. Peter’s profession of faith ("You are the Christ, the Son of the living God") is two verses earlier, while his name, a proper noun, is in the immediately preceding clause.
As you can see, Bob, this also settles the question of whether the word refers to Christ himself, since he is mentioned within the profession of faith. The fact that he is mentioned elsewhere, by a different metaphor, called the cornerstone (Eph. 2:20, 1 Pet. 2:4-8) does not disprove that here Peter is the foundation. Christ is naturally the principal and, since he will be returning to heaven, the invisible foundation of the Church that he will establish; but Peter is named by him as the secondary and, because he and his successors will remain on earth, the visible foundation. Peter can be a foundation only because Christ is the cornerstone.
Peter denied his Lord three times but Christ stood the test and fulfilled His promise of redemption.
Still reflecting on Matthew 16:19, Peter alone was promised something else: "I will give you the keys of the kingdom of heaven". You are correct in recognizing the important symbolism of these words. In ancient times, keys were the hallmark of authority. A walled city might have one great gate; and that gate had one great lock, worked by one great key. To be given the key to the city—an honor that exists even today, though its import is lost—meant to be given free access to and authority over the city. The city to which Peter was given the keys was the heavenly city itself. This symbolism for authority is used elsewhere in the Bible (Is. 22:22, Rev. 1:18).
Now, immediately before his denials were predicted, Peter was told, "Simon, Simon, behold, Satan demanded to have you, that he might sift you like wheat, but I have prayed for you that your faith may not fail; and when you have turned again [after the denials], strengthen your brethren" (Luke 22:31-32). It was Peter who Christ prayed would have faith that would not fail and that would be a guide for the others; and his prayer, being perfectly efficacious, was sure to be fulfilled.
Finally, after the resurrection, Jesus appeared to his disciples and asked Peter three times, "Do you love me?" (John 21:15-17). In repentance for his threefold denial, Peter gave a threefold affirmation of love. Then Christ, the Good Shepherd (John 10:11, 14), gave Peter the authority he earlier had promised: "Feed my sheep" (John 21:17). This specifically included the other apostles, since Jesus asked Peter, "Do you love me more than these?" (John 21:15), the word "these" referring to the other apostles who were present (John 21:2). Thus was completed the prediction made just before Jesus and his followers went for the last time to the Mount of Olives.
More fancy footwork with words to explain and clarify away what should be abundantly clear. Christ alone is The Foundation and nothing can change that. Galatians 2:11-14 shows that Peter is still the fallible person that we all are. You can dress him up in a fancy pointy chefs hat and give him a decoder ring and he still will be a fallible sinner such as you and me. Christ alone is perfect and He alone is fit to be the Head of the church. The Gospel is simple - submission to God and repentance for our sins through the Blood of Jesus Christ. But your church has made it all complicated with rites, ceremonies ,rules and hierarchies. I do not feel the Carpenter of Nazareth would feel at home in a statuary filled cathedral.
We will all be given the keys to heaven if are His followers. Peter was given no greater authority than the other disciples. He was re-instated with equal authority (in front of the other disciples) to quench any quarrels amongst the disciples. Peter had certainly been in hot water before.(Matt 16:23)This following Matt16:19 (Catholics favorite verse)which is really no different than Matthew 10:1-14 which outlines the apostles powers.