Here are some more important questions to ask along your process of research:
How would you describe his/her dependability on their parents? Healthy dependence is fine; you are looking for an excessive degree of clinging which can cause issues.
Does he/she smoke or drink? (For this, first ask for a yes/no answer. Only if it a yes should you probe further). Do not shy away from this question, as it is a deal-breaker for many, and can prevent dating someone you would never consider marrying.
Three important areas to assess are their stubbornness, stinginess and anger. If any of these qualities are found, it is a red flag. They are big hindrances to forming a healthy relationship, and will not bode well. Do not merely ask, “Do they get angry,” but, “How are they when they get angry?” “When is a time you experienced their generosity?”
Can he/she take charge of a situation? Is he/she proactive or reactive? Especially for a man, it is essential to discern that he is proactive and is capable of initiating. Is he capable of leading a family? If there is hesitancy about this, it may indicate that he lacks requisite maturity.
What importance does he/she place on dressing habits? Do not merely ask if they dress modestly. There are differences within that definition. Dig deeper and see how their attitude is to clothes. Some boys and girls may dress more formally or more casually, and you should explore this. (On dates, you will generally see their more formal side, but you want to know how they really are when no one is scrutinizing them. Don’t wait until after your engagement or marriage to discover this).
Why do you think they are emotionally stable and ready for marriage? This question is extremely vital. What is he/she looking for in a wife/husband? Why are they looking for that? Is that the way they grew up, or is that a newly formulated outlook that they developed in contrast to their upbringing?
And lastly, why do you think he/she would be a good match for your child? Explain, at some point in the conversation, what your son or daughter is like, and see what the person you are speaking to thinks. Their answer may surprise you when they say yes or no. You never know until you ask.
All in all, do not wait until dating to discover who the person you are looking into is. Ask smart questions wisely and gather as much information as you can. You are looking to gain quality answers, and do not move forward unless you have them.