CFive It's not nonsense.
Spleef, TnT run, and the Snowball arena are things in other games. They might add something similar to the snowball one, but spleef and TnT run are things that work in Minecraft because of how the game is designed from the ground up. It's not a concept that translates to party animals (small maps and ragdoll physics) so i wouldn't get my hopes up for anything like those here. You'd have to play them where they already exist.