How about a different character a season? That way you're more attached to them.

If they do a series 1) it should have actors, not animation 2) It should be in the same general area (I'd really like it to maybe explore Detroit)

Maybe a movie about the BOS's trip across the Continent ending with them walking into the capital wasteland where after killing a super mutant Casadin says "It's finally over" and Lyons says "No it has just begun"

I dunno, I wouldn't like it to be an endless series, it shouldn't be more than two seasons or something and that gives us only two characters. The idea of one new character per episode I got from that Band of Brothers episode with Blight, although he's not the main character you get to follow him, see him evolve and you get attached to him in a way.

Then I thought it would be cool if you got to follow a new character, different personality and get attached to him/her. His/her story will pick up after the first character's story, like they're in the same town or there's a problem/conflict with a faction they're both involved with (maybe on different sides) or anything. Things that connects them, but not directly like they know of eachother's presence. Then there could be characters that know eachother, or are related, like character 8 (that is episode 8) is the brother of character 3, who were out searching for his brother but ended up in some trouble and was possibly killed, but then later character 12 saves him, and in the same episode kills character 6. And in the end of the season, all the characters who are still alive would meet in some way or another and all loose ends would be tied up and... end of that series! (or just that season!)