vBulletins current system with infractions, reports, and user notes (I’ve never used the notes system) are not at all connected. My thought would be that instead of having everything seperate something like this would happen:
Users report a post -> Moderators recieve report and have direct options to use infraction system and on of the options in the infraction system is ban the user. Then remove all parts of the current ban system and just have it be a part of the infraction system.