hmm...
Paul in Gal 2:9, named James, Peter, John as the pillars, namely
the key leaders of the early churches...
James, Peter and John, those reputed to be pillars, gave me and
Barnabas the right hand of fellowship when they recognized the
grace given to me. They agreed that we should go to the Gentiles,
and they to the Jews.
reason is very simple, calling
elders at time serves 2 primary functions in the early
church;
1) as bishop/overseer of the church affairs, looking after the
fellow believers, something like the current Pastors are
doing.
2) as preacher/missionary, these are like the modern days teachers,
missionaries.... etc, doing the field works kind. 
so... bottom line is, there is no clear "leader of leaders" during
that time, except of course, all look to Christ as the head.
