You don't need any human work. A script can process all transactions and generate the winners. You would be able to run on a 99.5% EV and still be profitable - just run the script as normal on your computer.
Of course, there is actually writing the script, but if you're a programmer it just takes a hour of your time?
Yes. Getting it working is the hard part. But, I'm guessing there would still be human intervention at the time of the draw or at the time of determining the winners. I don't want the computer just automatically making a game, wait until the deadline, do the script for the winner, send the winnings, then start another game ... There is the danger of the software or the platform or the server getting hacked, and the private key getting stolen.
Actually, now that I think about it, I could just do the work part once a week, when I end one game, and start another. I've managed to make a spreadsheet compute SHA-256, but I'm still figuring out how to get everything from the blockchain and make a script or software do it all.
Anyway, my lotto has one player already. hehehehe... I have no idea who it is since he or she isn't posting in my thread. If you want a 50% chance of getting his 0.01 BTC, go play. hehehe.
Feel free to comment there instead of here, as I don't want to high jack someone else's thread, even if they've already disappeared.