Ok first of all, ditch the rubbish voidwatch looting system in WoE. It doesn't work. Those farming for coins never see the ones they want, and those farming for items have a very small chance of getting them. So here is my suggestion -
It is a known fact that SCH has the job ability Libra - they can see how much enmity each player has on a target. Allow a coin to drop into the lottery pool of anyone over xx% enmity at time of death per target.
ie. Assume the minimum enmity required for a coin to drop is 10%. Jack, John, Jill and Jane are fighting a crab.
Jack has 60%
John has 20%
Jill has 15%
Jane has 5% enmity during the time of death of the crab.
A coin drops into the pool of all 4 players, however since Jane did not have enough enmity during time of death, the system automatically passes the item, whereas the other 3 are able to lot.
This system will weed out the people that leech, along with allowing people to still team up - or solo if they wish. Teaming up will yield faster kills, therefore more will drop that they can roll on, whereas playing solo will guarantee that if a coin drops, it will end up with you.
I do see a downside to this however, and this is that I believe there will be less mages then there are currently - due to the nature of the job and it's goal to *not* hold enmity.
Quite simply - use a similar system to Bastion's exp reward system, only replace the EXP / credits with a lottable coin.
Where do items come from? This is when you can add the randomness of the voidwatch style rewards - open a chest to find random junk. Take coins out of this equation (perhaps keep pouches, but remove singles).
Currently as it stands - I do not have a WoE weapon, yet I have completed 4x empyrean weapons. The simple reason is why grind yourself away in voidwatch when you can grind yourself in Abyssea just as fast (if not faster) for a much more powerful end result.
As it stands, there is absolutely no incentive for anyone to do Walk of Echo's aside from a couple of random pieces of gear.