Naming a church tradition after its form of government has always seemed lame to me, but if we are going to do that, I recommend we describe the form accurately.

Presbyterianism is not simply a system of graded courts beginning in the congregation and ending at the General Assembly (let alone a political star chamber that they have decided to pass off their responsibilities to).  Rather, a presbytery is a regional body of pastors, who with selected ruling elders, rules over a regional body of churches.

There are graded courts in the case of lay people because members of a local congregation are accountable to a session.  But a pastor is a member of this ruling body called a presbytery and he is accountable to them.

A few links:

Church Membership of Ministers by Charles Hodge

Ministers and Ruling Elders Do Not Occupy the Same Office by Mark Horne

Should Ruling Elders Ordain Ministers by Charles Hodge

The Old Testament Precursor to the Pastor by Mark Horne

The Pastorate and The Presbytery by Mark Horne

The Relation of Ministers To Ruling Elders by Edmund Clowney

What is Presbyterianism? by Mark Horne