Would definitely make the server more interesting: https://www.spigotmc.org/resources/supplydrop-1-8-1-9-1-10.23455/ I dont know if its compatible to 1.11 though.
Adding onto @Silent Artemis idea: My suggestion would be to have a 20% chance of a supply drop each night (sort of like the fun rounds on TTT). The supply drop would always drop in the same designated area- ie. at 0,0; and a server-wide message could appear a minute before the drop to inform the players. This could help make the occasional night a little more interesting by drawing in players to a small area, thereby helping to increase mutual PVP on the servers in the survival world.
I'd suggest they drop every HOUR, not every night. Just to make it happen less. I'd prefer it drop on a random coordinates in the overworld( within 10k by 10k is the optimal ), not only people would go out and look for it, but they will have to survive PVE(freaking skellies are OP) and PVP.
Making supply drops in daylight would remove any risk involved, and if it where every hour, they would be dropping during the day far more than the night. As for PVE, I can drop into a pit filled with zombies and skeles, at least 40 mobs total, and will easily survive. Others can do the same. PVE isn't really a problem, especially on the overworld, where people can just use Elytra or ender pearls to travel mass distances in a few moments.
A little controversial of an addition, but it might be fun if the drops happened around or in certain claims, so long as the owners of the claims work with the devs to ensure they don't get to much of an advantage. Examples include the many cities people are building, my desert when it is completed and not just a mass of ugly. Or, alternatively, a patch of land that people can pay for a 100/100 space in in which they can build traps or obstacles
