i'm late to this thread, apologies
My take on companions/ followers/ RPC's recently has been a similar compromise to what's been discussed in the thread before:
on the one hand, i use fully fledged companions. They are very detailed characters designed with their major purpose, to join the player, in mind. They can be linked very strongly to the plot, have their own motives to join and have an extenisve background, bicker with each other, have likes/ dislikes and so on. On the other hand, there are "light" RPC's that are not as detailed as the full RPC's for various reasons: Writing and doing the VO for a full character takes much more time, while there's a certain risk your player doesn't even figure he can recruit the RPC and most of the work will be left unnoticed by the player.
So various NPCs can join the party, but are not designed specificly to join up. For example, any character whose relevance to the plot is over, e.g. his quest is finished, could theoretically be a "light" recruitable. He may have asked you for help for a problem in the past, and as you solved his problem, he feels he owes you more than his puny quest reward. While he doesn't wanna join you, if you insist, he will because he owes you. (from a game design point of view, an NPC whose quest was completed doesn't serve much of a purpose otherwise anyway... IMHO). Surely this peasent has less raw combat skills than your battlehardened veteran (tm) that you picked up, but he may know things (guide/ exposition) may know people (interaction bonus/ help) may have other valuable skills and helps lugging your loot around
I disagree that all these "light" recruitables should be of the mercenary type. Even in a grimdark dystopian world, money is rarely the only reason to fight. people regularly bunch up in groups to feel safe, to fight an outside threat, etc. if you need the money for balancing purposes, pay them an upkeep for their food or something, rather than the slightly overused "heartless old mercenary will do anything for dollas (but turns out nice guy over the course of the adventure) "
i very much appreciate your take to use direct control. AI controlled companions are simply a nuisance. I'd rather roleplay all of the party members than have an AI roleplay them.