(Nate is the default name of the male lone survivor just FYI). So On my adventures through out the wastes I've made it to the brotherhoods airship and had a meeting with Elder Maxon and so far most of the BoS have treated me like a a regular wasteland schmup. Other than mentioning that I'm from a vault, pipers interview, and telling the dipstick in diamond city that's not how baseball is played, nate's background at least at the point i'm at in the game isn't really brought up. Normally in fallout games (at least 3 and NV because those are the ones I played) your past is left pretty vague and for the most part that's ok as in those games had an "insert yourself" protagonist.
But in fallout 4 we have nate, a voiced protagonist with an actual background and ties to the pre-war world. Not saying a defined protagonist is bad for a fallout game, but if we are going to have this "character luggage" don't you think it'd be a a good idea to have it be little more influential on the plot/interactions around you? I mean this guy is from the pre war time that isn't a ghoul or brain in a jar, and mentally stable to boot. And he was even a part of the pre war military! With of all the useful knowledge he could have had at his disposal, think how much credit he'd have with brotherhood with that. Sure they might not believe him at first, however it would have been really cool mission to say show them the vault you were in and prove that you are from the pre war time, and as a second quest you could do something that only someone of your status could achieve, like say getting in to a secret bunker the brotherhood is stumpt to break into by knowing the right password, or being able to correctly decipher some pre war holo docs for them and make them realize, "Oh crap, you're the real deal."
Not only for faction interaction, I don't really see nate's history being taken advantage of. Even if it didn't influence the plot in a major way, think how cool it would be to talk to people/companions about your life, giving a more in depth background of your character and expanding on the lore of the world with you being living window to the life people in the commonwealth only can speculate about. The line: "Families service to the country" opens a whole can of possibilities to story telling, you could have been a foot soldier, a sergeant, perhaps you were a military scientist, or heck, you could even have something to do with the oldworld nuclear program.
Perhaps the part of complaints of a voiced protagonist stem from the fact while being voiced, he still handles like the "Insert yourself" formula and falls flat with all the missed opportunities that a real/defined character the protagonist could have brought.