I was thinking there should be survival missions which would be in a huge area with a group cap of 10 players surrounded by spawners (including a ton of extras like Tortodrones, Soul Jellies, Fallen Knights, Gourdlings, Creep Cakes, vog with a 1% chance, ironwood sentinels, void creatures and the swarm), while they still drop crowns, AND if everyone dies and doesn't revive in 30 seconds, the survival ends but everyone keeps there heat and crowns. It'd surely be a great implement, and thanks for reading this post!
add survival missions
@Gingermace: A bit short of a response, but completely right :P
@OP
Reason(s) why it's exploitable:
The "better" SK players will form top-skill guilds where they just endlessly farm crowns in the arena. Due to it being in the same depth (as it appears implied, correct me if I'm wrong), elevator costs are minimal and with enough skill and the right set of equipment, a group of talented players could practically fight endlessly and earn tons of crowns in the process. I've thought of similar ideas, but there's really no way to make this work when the enemies have drops. Even without drops, it would have great entertainment value without mist, so you could theoretically be mist-crafting and still enjoying the PvE combat of the game, which is not what the game was built for.
Exploitable. That is all.