I will say that Lorna and Magneto and Wanda and Magneto's relationships have been in flux of late, though before their most recent story lines things were more settled. Pietro and Magneto's relationship in contrast writers seemingly are much more on the same page about. Father disappointing in his son... son angry at his dad. That is what they know better then father-daughter relationships.
Male writers I suspect know sister-sister relationships the least, hence why Wanda and Lorna have never really talked in depth in the 616 on panel. Its not like they haven't had many of opportunities going back to the Genosha era. This pretty much defines the Wanda/Lorna relationship.
Noticed that too, totally with you on that.
Would be nice if Magnus will interact with his children more in his series and now in ANXF. There can be a nice opportunity actually.
PAD likes to do his own thing and while its possible Magneto might come over in time I tend to think the Magneto ongoing is the more likely place for those two family reunions as its not a team book, its a solo story centered around Magneto and his life.
As Wanda and Lorna I think that one on paper has a large amount of potential, but I think that one is going to wait for Marvel when they are going hog wild trying to find stories for Wanda (mid next year and onward) because of the film franchise to do the story. Its a potential storyline that might be staring them in the face, but writers as I said tend to prefer to write what they know.