mcMMO stats only factored in up to level 1000. For example if you have 1200 unarmed, only 1000 of that level counts towards your combat level.
Min combat level: 0
Max combat level: 100
Chat prefix with combat level, configurable colors and toggleable.
Combat level displayed above head using scoreboard, configurable colors and toggleable.
Setting the "enable_tag_level" configuration option to false without restarting the server will not prevent currently connected clients from still seeing the tag for a while.
No way to reload configuration without reloading the plugin or restarting the server.