That said I do not think making story choices part of the character concept (via background choices or via various career advancement choices like classes and feats) makes story unimportant it gives the player agency over elements of the story that is all. If I was playng an Aes Sedai from the world fo the Wheel of Time it would be inappropriate to NOT have that bondmate and that character/class needs designed with that in mind... just like if you were playing Druid in 3e and you get a bear.
Ok, so there is a (potentially) big difference in 'getting a bear' and 'getting a follower', and that is that 'getting a bear' is not something that people normally do in real life, but getting a friend, or a companion, or a body guard, or a retainer, or a heir, or a student, or what have you is something that happens all the time in real life through very natural processes of communication based on mutual self-interest on the part of all parties.
The problem with making "career advancement choices" the gateways regulating these relationships is it assumes that forming relationships is not a part of play. In other words, it assumes that PC's don't get married, don't hire retainers, don't save peoples lives, don't form partnerships with NPCs, don't protect the innocent, don't have children, and generally don't cultivate relationships as part of play. In other words, it assumes role play very much isn't a part of play and that no matter how rational and reasonable it is for a relationship to form between a PC and an NPC, the GM will just say no because all relationships have to be paid for in abstract metagame currency.
But that is terribly destructive to play. Dick Grayson doesn't become Bruce Wayne's ward because Bruce Wayne's player decides to forgo gaining more ranks in judo or lockpicking or whatever in order to pick up a retainer. Dick Grayson becomes Bruce Wayne's ward because Bruce watches Dick's parents get murdered in front of his eyes, and then the two form a relationship based around the mutual desire to bring the culprit to justice and the mutual understanding they share as both orphans. So if Bruce Wayne reluctantly buys more Judo, am I supposed to kill this plot line?
PC's in my game develop relationships with NPC's in surprising ways that I don't expect through RP. And when roleplay leads to the reasonable conclusion that the characters have mutual respect for each other, and it is advantageous for the NPC to take employment with the PC and the NPC's motives align with what the PC asks of them, then PC's a friend. What am I supposed to do, block that just because it hasn't been paid for in currency?
The whole mindset here is busted. If a PC finds a magic sword, must they spend some sort of career advancement currency before they can keep it? If a PC finds a pile of treasure, must they spend some sort of career advancement currency before they can say that they have resources? If a PC impresses a high ranking noble who is a peer of the realm, perhaps by saving his honor and the life of his son, and because the PC has impressed the noble the noble wishes to take on the PC as a vassal and bestow upon him a title and manor, does PC the have to have some sort of career advancement currency lying around to allow this story to reach its logical conclusion? If the PC woos a wealthy heir and has high charisma, and roll plays out some sort of love triangle, which comes to some conclusion when the rival is revealed to be a dishonorable cad, and the PC rolls a series of fantastic successes with his social skills, does the PC need some sort of career advancement currency to successfully marry, gain station, gain income, gain allies, and so forth? Or can we just let the story happen as it logically ought to?
See the problem with making that cost abstract career advancement capital is that you both will tend to have players trying to cash a check that they have nothing to withdraw on, wanting to buy something and get it delivered now for which no story exists, and secondly when they do pay that price for it they tend to get really upset when another player simply gets the same sort of reward for free having acted out the story. It's all right and good to have a 'Marry the Princess' card or a 'Receive Lands and Titles' card in some sort of game that is about something other than RPing, like a strategic board game where the players are competing with each other to have the most reknown points at the end of it and we don't really care about story. Such a game is basically Monopoly with a different color and different text on the 'Chance' and 'Community Chest' cards. And that's fun for what it is, but it isn't a very great RPG.
So as for offering all these things as 'a choice', I'm totally for it. As for thinking you can handle the complexity of a network of social relationships with something as inflexible and simplistic as a feat, I think that's entirely bogus and ultimately problematic for any game more complex than a weekly competitive treasure hunt.