For me, it's always the reputation. Everything stems from it so you can't really go wrong, they wouldn't have a good rep if they are cheating their customers or if they are being rude to them right?
Well, that's the shortcut but it's a fact. If someone would want to stay safe then check out the reputation of the casino. You'll get to see people telling what's good about them and will definitely support and recommend them.
So I am pretty sure that reputation would be the greatest indicator that something is right with that casino that we are choosing.
And that goes with the reviews of the other gamblers but still, you need to check if those are legitimate reviews then because the fake reviews are also rampant. But in here in crypto gambling, majority of us here knows what are the good and bad ones.