I have appreciated Dr Larry Perkins’ reflections on leadership in the New Testament. He has a range of excellent articles that have appeared in his blog. Here are some links to the main articles.
The Shepherd motif – Pastoring (Ephesians 4:11)
The gift of piloting, navigating or governing (1 Corinthians 12:28)
The leader as supporter, sponsor and protector (1 Thessalonians 5:12)