A tool I use for planning my Tabletop RPG game campaigns is "TiddlyMap". It's a plugin for a piece of wiki software called "TiddlyWiki".
It's very flexible in the way it allows you to add nodes to a map, and connect them. It's almost a graph-drawing tool, rather than a mind-mapping one.
I suggest just going over and having a play at http://tiddlymap.org/ . There's no download needed, it all runs in the browser.
Fair warning, there's a bit of a learning curve to TiddlyWiki. However, it's pretty straightforward for basic usage, and the documentation is excellent.
Here's a free-and-open-source "pinnable comments" mapping software alternative to the aforementioned LegendKeeper:
TiddlyMap.org which is based on TiddlyWiki, a personal wiki engine that's based on one HTML file which you can host yourself on github.io
Not as pretty or easy-to-use as LegendKeeper, but you maintain absolute control over your own data if you're willing to learn how to use TiddlyWiki.
One approach would be to use "TiddlyWiki". Each image can be an "Image tiddler" which would include all the details as text, HTML or Json. Each image can be tagged with names, subjects, years, etc. A graph network (a TiddlyMap) can be put together of your family tree, with each image linked to this as nodes. This can be put together on your computer or hosted on the web.
The whole thing is free and open source.
Had to take a week or two off for holiday nonsense, but I'm getting back to work soon. Next release will be Filth-4, which is extensive, so probably a month or so? There may be another release before it along the way.
I think there's easily a 1000 or more hours into FQ. I've been working on it since mid-2016. But you don't need to know programming at all to write your own CYOAs. I just did because as CYOA, Fool's Quest is enormously elaborate and required its own engine.
You could get started using Twine. I don't use it, but I know Academy of Fetishes did. My own plugin would probably be easy to use to. I've built it with the intent of releasing it if anyone ever showed interest. You basically build your CYOA using Tiddlywiki, and optionally visualizing it with the TiddlyMap plugin. My plugin generates your CYOA from that with just a button click.
I use TiddlyWiki and TiddlyMap to organize and visualize my notes, respectively. I have a few levels of Tiddlies (entries):
Global and Gods
Regional / Cultural
Area-specific
Individual Entity
The middle 2 usually get put on the TiddlyMap.