For me simple and selective or unigue games is good because having lot of games will make the site looks not familiar eve after many uses.
Having instant deposit and withdrawal for crypto currencies will make them as good one.
I have never received a prize of such a volume so that I would like to withdraw it immediately after a win. Based on this, the immediate conclusion is not so important for me, but the reputation of gambling for me is in the first place, because it is on the rating that I react the most to be sure that no one will deceive me.