I know this server is a PVP server, but seeing it has a lot of bosses, I personally think some little mini-games might be fun.
Make an area with a boxing ring. (Did the same thing with my friends on a 317)
Make it, that when you enter the area, you can't wear anything.
Then, on the wall, add something that when you click on it, gives you boxing gloves.
Then you can pvp in the ring with boxing gloves.
When you leave the area, this can only be done by entering a portal, the boxing gloves are removed.
Anyways, It's just a little thing that makes a server unique and makes it attract more players.