S1, when my kids were dating there were specific questions that I asked. I wasn’t really interested in turning over every stone and finding every skeleton in the closet. But the answers that I needed about the parents were this. “Will they be good role models for my children and grandchildren”. That was very important to me.
Any good marriage is a result of hard work. It is also a result of each spouse putting the other’s needs before their own. You don’t need a crystal ball to tell you that if you do that you will have a good marriage. You don’t need to have a Rav hold your hand to do these things. You might need to be reminded by your Rav every once in a while that YOU are not the most important person in the equation, but those are the basic rules for a good marriage. I also don’t believe that marriage is about “give and take”. Marriage is about giving. If you both keep giving you will both keep getting without having to “take”.