Gladiator Arena 

Before entering the actual arena you will be able to select a kit. Each class is a little different but they are still similar enough to make none of them overpowered.

You'll spawn in a cage. You can open the cage gate by pressing the button and then enter the arena.

https://www.mediafire.com/file/49cfdz6vdtdl4sh/Gladiator+Arena.zip

BasinPVP

Before you enter the arena you can customize the colors to your choosing. There are 16 different concrete colors and you are allowed to select up to two different colors. If you aren't satisfied with the result then you can reset it to its default setting (expect some lag) and then choose two new colors. 

https://www.mediafire.com/file/dn84h6gncc7blfn/BasinPvP.mcworld