@Valgys On the subject of economy balance, you should remove a small percentage of the jackpot (like 1%-5%) before dispersement to control the availability of valuable items. Think of it as an application fee of sorts. I'm pretty sure the winners wouldn't care so long as the participation is high.
And then if you're ambitious, use the collected fee as a reward for a different event for the whole server (pvp games, 1-3 place in building competitions, first in completing a challenge, maybe even limited use slot machine that takes yet another currency/item to play to diversify your player-gathered resources, etc).
You basically gave yourself access to a ton of resources without generating it out of thin air like the issue with the casino. You should skim some of it off the top lol.
The application fee is the 1-5 blocks that you spend in order to get the off-chance of winning, that's how lottery works.
I don't want to lose any of the reward to "controlling the availability of valuable items" All of the items I would get are legitimate items that have been in circulation before being dropped into the lottery.
If the reward deducted from the lottery has actuall use, such as a building competition, I would be in agreement. But if the participation in the lottery was low, it would take a while with a 1-5% deduction from the lottery to get those resources. Assuming 300 people all pay 5 diamond blocks to the lottery, that would mean 15DB (1% deduction) at least and 75DB (5% deduction) at most would go to a building competition. That's a very small number compared to the 1500DB the lottery rewards. That amount of participation in the lottery is quite ambitious IMO and I doubt that will happen. Assuming 50 people donate 5DB, you would get 3.5 daimonds at least and 2.5DB at most for use in the competition. Very small amounts for a reasonable amount of participation.