I'd like a system where you get followers for free and train them up from shitty to useful. If they die/disappear, they disappear for a few hours and then appear later in a random encounter with the standard "I WAS JUST WOUNDED, YOU ASSHOLE. THANKS FOR LEAVING ME IN THE DESERT TO DIE. Okay fine I guess I'll start following you again you do look pretty badass in that leather jacket."
When you have your follower - you talk to him sth like that: "If something bad happens and we get divided, meet me at the base/tent/town* etc.