When Moses uses the metaphor of a rock, he thinks of the connotative qualities of enduring, unchanging, solid, awesome, strong, majestic, and beautiful.
Although Peter was given responsibilities of leadership, as connoted from the rock imagery or symbolism, he was not granted the post of 'vicar of Christ.'
To tear down cherished institutions is to leave a nation culturally ruined. God's people, in choosing the old pathways, tread the roadway to eternal life.
Of all the disciples, the one that we usually consider to have the most personality is Simon Peter. No other disciple's words and actions are so often recorded.