Without attempting to produce the final answer to the question, I offer the following observations:
- The clergy are human. I know some people don't believe this (indeed some of the clergy themselves don't believe it), but they are. This means there is no ontological difference between the question "what is the role of the clergy" and "what is the role of people in all kinds of ministry".
- The parishes that the clergy serve are enormously diverse in their situation, character, needs, and aspirations.
- "Vicar" is a job description, but this is only part of what it is. Ordination is an attempt to recognise gifting for the benefit of the church, and gifting comes from the Holy Spirit who provides the huge kaleidoscope of gifts in the body of Christ, in which no one member is the same as another.
I encounter a lot of dogmatism on this question, with all kinds of people pronouncing on what the role of the clergy should be in the future. It's good that we are thinking about this, but the idea that we should create a standard model into which all parish priests should be moulded is very silly.
The rapidly shifting situation that we now have is a great opportunity to promote diversity in ministry. There's still a need for pastoral priests with a sacramental, incarnational ministry. There's also a need for creative pioneers who can push back the boundaries of conventional church. There's a need for leaders who can hold the breadth of vision needed in large urban ministries. Read 1 Corinthians 12, Romans 12, and Ephesians 4, and grasp the multi-faceted nature of the gifts.