Here is the final product, at request I've added a few more trees to the area and have given the upper seating area a few more seats, I'm not sure how very well utilized they might be, but I hope that one day we will be able to fight in the actual arena itself with player vs player so that that area might see some love.
I've provided in the zip folder all of the necessary files and a picture detailing some locations I'd intended NPCs/Entrances to be, I wasn't quite sure how to make entrances and exits on a singular map so I apologize.
Courtesy of wonderful Slydria there is also a new overworld icon I have included as well, many people often misconceive the arena to be inside a tent currently so this would be a good way to update that too.
If anything else is required please feel free to PM me or ping me in the mapping channel on Discord and I'll do my best to provide.
Edit: Don't mind the map file's name, feel free to rename it, as I forgot to.