It's not a bad plugin, but a large amount of features don't work.
I've come across a few issues that I'm hoping you can help me with and after troubleshooting them for a few hours, I cannot seem to find a solution.
I'm afraid that the coin shop feature does not work.
I've enabled it in the files and both myself and other players cannot get it to actually give us the items when we're in it.
Name tags won't disappear
I've also removed name tags from the arena files and config, but they still appear in game.
Some stats don't register for players
Some people with all the necessary permissions to do everything in paintball don't get stats (screenshot below)
"HolographicDisplays" plugin no longer working (New support request)
I'm afraid that Holographic displays hasn't worked since 1.13 and hasn't been updated since December. Might it be possible to add support to "Holograms" by SainttX?
https://www.spigotmc.org/resources/holograms.4924/
No listed servers use your plugin
I noticed that none of the servers you have listed use your plugin or exist any longer, so I couldn't test my issues by comparing it to other servers. You are welcome to use our server as an example if we can get your plugin working as intended and have already worked additional arenas into our project timeline.
If you'd like to test it on our server to see for yourself, we're set up at "mgmc.me" and you can get access to the paintball arena using the warp "/warp paintball".
Screenshots listed below:
Nametags displaying still:
https://1drv.ms/u/s!As49I6llCdbJnBIfMZsusKkl29he
Stats not showing:
https://1drv.ms/u/s!As49I6llCdbJnBMfGom4rAPG8YU_