@ztlxltl Don’t be sorry for anything… The work done so far work is really impressive. Take what you want from what I say, and implement it at your own pace…
Regarding my point about the expander for the non active spouse, I was not clear: I was speaking of the expander to the ancestors (upwards). In your example, even if Josephine Pelletier has ancestors, the upwards expander wouldn’t show (as it is in your screenshot). I don’t see a reason for it.
I’m not sure I understand the answer to my 1st point, why should it create crossing lines ? That is, unless you don’t want to change the layout, which can be a choice.
Concerning the rules, I don’t have a particular idea, there are already some which may be enough.
And another thing I’ve been forgetting since I started commenting: can you add a way to change the default zoom level whet you first start the view at Gramps launch. For me at least it is way too big, and I have to zoom out each time.
That’s all for today (and the week-end also)!