Hi, I hold a few tokens of varied nature and a few coins. I have setup a few eth addresses for the younger members of my family. I am talking about kids that are less than 3 yr old 
So, what would you include in their new accounts, so that they can use it in 15 yrs?
Just use list of top 20 from coinmarketcap. If not all these coins will be successful after 15 years, definetly most of them will grow. So, what would you include in their new accounts, so that they can use it in 15 yrs?