Very nice resource, found no issues with it. But I got a suggestion, maybe add /coliseum join, /coliseum leave, so it teleports you to previously defined location when joining, and to the location where you were earlier when you leave it? Otherwise, 100/100.

Hey, you are doing really nice! This is a very good plugin, especially considering that it's your first one :) You did a nice job creating the support server as I suggested. Keep it up and you'll become advanced in no time!