Maybe it can help to diversicate this situation, although it will be tougher to code and write:
- you can add a positive and a negative feature to a good/bad relationship, e.g. some stats rise while others fall or you get different boni/lai on skills. This will not "cheat" your companions because of boring stat maximazation but it can individualize them, as long as the positive and negative parts balance each other out. E.g. Rebecca might get better survival skills since she believes she cannot rely on you but on the other hand she gets a malus to social skills because she loses hope in social relationships and prefers to stay on her own.
- you can set up different situations, where your companion gets different boni and mali depending on the action/answer you chose in this particular situations so you can go around the "long time goal" and focus it more at the stressy choices at hand. This can be a mini game in itself, when you have to guess which answer/action will lead to which development since a companion does not tell you everything about him/her from the beginning. Maybe after you left a squad of
militia for dead to make a run for your life, an NPC might say "hey, I understand this. I had to do the same decision 20 years ago but did not speak to anyone about this. You can talk to me about your guilty feelings if you want to" and his/her affection rises.
But in this way the situation at hand has a higher priority than the "endgoal" and you are not forced to be bff with everyone (which is kinda worn off since you have to be bff with every companion in 90% of all rpg). It might help to add some contrary charasteristics to the NPC so it won't be too easy to anticipate the effect of your action/answer. But I think this can be fun for the writer to do
. If your writer is into it, you can set up a few contradictionary situations where the player just cannot get a good result from all of them and has to think about which way he/she will follow.
In general I would say - it is essential for this kind of relation ship baes skills/stats that everything has a good and a bad side. I did something like this in a decision tree for a P&P game a few months ago and it got more interesting for the players when there weren't just "good" or "bad" choices but also a great "grey space" where you could not clearly distinguish good and bad from another.