How far did you do for each of each choice like life and death decision or no? I am just being dramatic. What tries I to ask you is what is your scopes and criteria which you are considerate meaningful.
Well, not necessary life or death, but say we take back Bob, if the only change is that he's wearing a green shirt instead of a blue one... Sure there's a difference, but it has no impact other than visual (well unless that was his lucky shirt and a lot of special stuff happens to him just because of that green shirt). So that's not much of a branching "story".
Basically I think the question is not to branch or not, the question is : at this point X of your game do you have a need to tell a different story ?
I can take as a simple exemple a very small branching for one optional party member on my current project who has 3 different "introduction" cutscenes (if you do find her at all is).
1st case : You have her friend in your party, that's the best situation you can hope for, as it makes it easier to find her, and if you get there in time, it's a nice reunion.
2nd case : You don't have the relvant party member, but you still manage to find her in time. It's a tougher path, requires a bit more luck/instinct/research to get there, but eventually you'll get introduced and she'll join your party.
3rd case : You do eventually find her, but you're to late, you just find her body and imrpovise some funerals. (and there's also a micro-branching there, as if her friends are with you, then they recognize the body, making the scene sadder).
All of those cases actually don't have a huge impact on the main plot (thus the fact that it's optional content), so it was relatively easy to add. And I actually didn't planned for it before starting to code the events. It just made sense to me at that time considering the circumstances. But you can see how a very small simple thing can become quite the extra work just because of branching.
When you recruit a ninja into your party, you will automatic not allow recruiting a samurai because they are both have a disagreement on combat philosophy.
I guess I have to create a relationship system, too. Pacifist vs Militarist of team members.
When the bar to the lowest point the members will leave the team.
There you're more on a game design point of view. Of course if you want to do that, go for it !
The branching story part comes when you choose what to do with the situation. Think about how important those characters are to your story ? What are the consequences of having one or the other ? What happens if one leave ?
Could be that they don't make much of a difference (easiest way obviously), could be that they open up two completely different stories. That's up to you to decide what you do with that idea.
Do you still time writing a lot? I am not the most organize and perseverance guy on Earth. Are you are a professional writer?
I don't think I'm awesomely organized. Also, my branches have a lot of convergences too. So I don't have dozens of different stories, just one "core story" with different outcomes and different ways to get there.
As much as I like making stories, I'm not a writer. All I can offer is my own opinion and expericence. Maybe a true writer would have a different opinion and a easier time dealing with the writing part.
I actually tried starting to write a novel about 2 years ago. I eventually gave up and went to game making (lol). Writing a book is so much more than just telling a story. It is really not easy to get done right. You need to find the right words, the proper way to take the reader in, do some research, sometimes mess with the chapters, read what you've done, rewrite half of it, and so on. lol