I will register all of my domains for a 50 year term. This will assure and guarantee that I will have my domains for the rest of my life. If for some reason I should live to be more than 100 years old, I will continue to renew the domains, and if I have the resources, I will register for another 50 years.
I will keep all of the current domains I have now. However, since I will have 3 businesses, I will need 4 more domains. One domain will be for the umbrella of all of my businesses, and then each business will gets its own domain. Even though I can no longer do actual web development, I will continue to use the WordPress platform, and will likely keep the current theme I use for all of my domains. An exception will be to consider paying the theme developer to drop its promotion that is in the bottom right of the content line. If the developer will not be willing to make the customizations I will need, then I will look for a WordPress theme developer.
Since I am over 50, a 50 year acquisition of my domains will allow me to be older than 100 before I will have to worry about the domains. It would be possible that I will be deceased by then, and the person that received my inherited businesses will be able to deal with the registration unless they sold my businesses, or run them into the ground. As mentioned, if I am still alive when the domains will be due, then I will acquire another 50 year term.