The existing tournaments implementation functions using parties and has parties queue in, and then the tournament can be started, with bracket generated.
In a proposed draft mode, Captains can be either manually assigned by staff, or queued into similar to a role queue.
Players who want to join the draft as draftees can either enter using the typical join button, or joining the voice channel if that entry mode is selected.
Once the requisite number of players have joined the tournament, (or if the staff decide to manually start the tournament/draft selection process), captains would take turns selecting players utilizing the same pick order options that exist for regular non-tournament queues. Once the selection process is complete, the normal tournament processes would continue, where team voice channels are created, a bracket is formed, and matches are played.