Before joining an online casino there are several things you need to consider. One of them is whether the casino is licensed or not. How is the security of that casino site? A good casino can be selected after carefully observing their various promotional offers, their withdrawal fees, customer support as well as terms and condition etc. are very much important to find out a good casino site.
Do you mean that we should avoid non licensed casinos although there are some reputable non licensed casinos? We can make it simple if you ask me, this forum is more than enough for us to choose which casinos are good to play. We can check the feedback from real players, review from reputable bitcointalk members, etc. I would put promotion and withdrawal fee aside first, reputation is better than promotion.