Speakers should be approved by the local board and (the theological aspect) by the pastor, local ministers, or elders if applicable, based on:
A speaker’s outside affiliation should be noted as a courtesy but no advertising or promoting should be included in the presentation.
Personal experience must not be suppressed but the speaker should not use them as a point of authority or express what was received through them authoritatively (unless a process is in place for the Church to approve mystical revelation as with some other Churches).
We must not become the model of the Orthodox Church suppressing the individual while balancing this with the need to maintain the integrity of the group’s expression of the Teachings.