For your estate plan, you have decided to create a trust, rather than a will. Why? You have your reasons, but a big reason is your concern about the spending habits and lifestyles of your beneficiaries.
As long as you have known them, they have not handled money in a prudent manner. Financial responsibility has not been their strength. They have splurged too many times, buying expensive things too quickly without thinking through the purchase. Some heirs also may have substance abuse problems. All of this makes you nervous, especially since you have a sizable estate.