For an online casino, I look first if it's legit/trusted casino with good promotions, deposit bonuses, fast deposit and withdrawals. good customer support that can answer all my queries and concerns quickly and of course the loyalty rewards that will make me stay or stick with that casino because I know that they give good perks and benefits with their players.
You actually have a good criteria which you do look out for but one which I think you shouldn't place at priority is promotion and deposit bonuses because even scam projects can be promoted very well and you will not suspect that it's in any form fraudulent and isn't a good project to follow up although their promotion last within a short period and after they must ha e reached their target audience they may stop the promotion. Some Gambling sites can actually be fraudulent in their activities but yet the may have good and nice looks when visited so you don't get to suspect they carry out such acts.
For good sites where you can be sure to be safe both with your funds and identity, check out the gambling sites been advartises here on this forum and you will get to find some good ones that you wouldn't have to go through the stress of further verification to be sure about their authenticity.
I have a perception of things that are actually Somewhat similar to what you say about that , so I use them and stuff like that. I'm very reluctant about it, because I don't really trust bonuses, for my bonus it means one thing and for casinos it means another, very focused on doing many difficult, almost impossible things in order to get the bonus, therefore when I am in a casino what I do is first play with my money and without taking any type of bonuses, It is my taste, and due to my experience I do it this way, for the rest I respect the position of each player, there are some players who are capable of being happy with a 5x, 10x to be able to withdraw the Balance that the casino Gives , for that Reason I am a person who is not Very given to accepting bonuses, I have had many Experiences.