Rollbit casino has received 3.6 out of 5 rating from me.
Also, the KYC requirements of this site as you pointed out are clearly messed up and are a big issue(Especially for whales). Overall, another great review!
There is an explanation in the review why I think that welcome bonuses are important. The thing is that most of the casinos just don't know how to create a deposit bonus that will be both appealing for the players and not too expensive for the business at the same time.