In the past hour I've made a fairly simple gamemode based off of the gold collection idea. I might go on to code your concept in full, but this demo is actually pretty fun to play. The premise is that when you spawn, you have four gold automatically on you. You kill other players, and you get their gold. As your supply of gold increases, so does your speed. It caps out around 50 gold, and your practically zooming across the map. But, the second you die you lose your gold and speed. I even designed an emitter, that activates when you get a lot of gold.

The concept sounds interesting after a bit of clarity, I'll take it apart and see what I can do. Changing a player's shapeName is pretty illegal and I'd rather not do it (gold counts). I guess players can tell the ballpark of how much gold someone has by their speed. I'll start a demo of the building one. I like the idea of only the hunters (pshh, names) being able to jump, maybe I could even elongate their jump a bit to combat fortresses or something. Hut-building would be a problem, and I'll look into ways to prevent it.
Edit: The feature where when destroyers touch actual bricks they die isn't very feasible. I can't find a way to do it. fxDTSBrick::onPlayerTouch only works with bricks that have events on them.
This is another edit. I've created another gamemode, no pictures this time. It's called Oddball. Basically, at random, a player is selected to be given the oddball. They'll be a bit faster, and have a glowy trail. They then run around the map, and try to not die. On the occurrence of their death, their killer receives the oddball. It's pretty much a scramble to be the last person to have it. The one who has it at the end of five minutes or so, wins the game.
Okay I lied. Here's another picture. It's going to be the emitter for the oddball carrier, which is why it's so damn annoying. I'm probably going to change it from shooting out all around you to shooting out from your back, like a regular trail.
It's a bit too long to post here normally...