Sikhi is said to have no priests but how would you define your religious leaders, what group or groups most closely fits this role and in what capacities for each?

Sikhi has priests but not priest class. Two are distinct. Anyone can become a priest and perform the religious ceremonies. There is no certain group that has this right. The authority to make decisions rests with the Five Beloved Ones who are chosen by the entire community collectively. Any decision made must not go against the message of Gurbani and traditions of the Khalsa. The decision is not absolute. Only Gurbani’s injunctions are absolute.