I love this business model. I have invested a bit and will probably invest more. I'd like to make some suggestions:

1. Maximum bet should be whatever gives the highest return to Just-Dice (following the Kelly Criterion). Not only it increases our expected profit, but it attracts more people looking to hit the jackpot. And people hitting a gigantic jackpot is also great for marketing. If some risk adverse investors prefer to have lower returns and volatility, they can simple divest a portion of their actual share. Another option, if it's cheap enough to implement, would be letting investors choose how much they are willing to risk in a single bet.

2. Customers should be treated with much more respect. Stop calling them "whales" and that kind of things. You are doing exactly the opposite of what "serious" casinos do, specially brick and mortar ones. Customers must feel comfortable betting at Just Dice. We have to try to make them feel good even when they lose, so it's more likely that they come back. People don't like feeling stupid.

3. I don't get why some of you complain so much when some customers make a lot of money. Don't you understand that they are losing in the long run? I wish we had thousands of high rollers gambling all day. They win sometimes, it's inevitable, they wouldn't be willing to participate if they couldn't win. Every time they bet, we win 0.01 of that amount, that's the only thing that matters. There's no winning strategy, each bet has the same negative expected value. The only thing that we must care about is people being able to bet profitably, by knowing what the dice result will be.

4. We should give more options to customers. For example, whether the next dice roll will be odd or not. Or whether it will finish with a 5. There are lots of possible options. I know they can be "made" by defining the chance you want to have for the next bet, but there's people that prefers to bet on something else than higher/lower than X. Or, even better, add more casino games, using the same bankroll.