What are you allowing with your money is a lot tougher than just asking for money. If you are bankrolling the casino so that they can offer bigger max amounts that is a lot more important, but if you are asking basically for partnership and spending that money on everything from bankroll to staff to marketing and other stuff I am out, I won't invest to it.
You may think that is less around but with dapps and other stuff there is really a lot of people who are actually doing something like that, they care their own coin or token and what not and they tell people to invest into it and with the coins they sell, they are basically making you part owner of the casino but also spending that money on whatever they want. That is not something I am quite happy to invest into.
It depends because some casino do show off transparency when it comes to house profits.You can calculate on how much had been generated with site stats.
When it comes to expenses like staffs maintenance etc. then its on house responsibility and come to think that bankroll investment is different from company share or something like that.
Lets talk about bankroll investment then i would say that if investors doesnt mind too much in terms of how small your gain is then this would be also a considerable choice
but if you do expect for something big then this wont fit out on the list.