After the retcon, she lost those storylines. Until X-Factor in the 90s, all of her appearances afterward focused either on Lorna being Alex's girlfriend, or Lorna being possessed, mind-controlled or defeated, constantly putting her identity as a character into the service of making other heroes look more heroic and villains look more villainous. Her tie to Magneto, before her re-establishment as one of Magneto's daughters, gave her a huge boost in focus after the Genoshan massacre. I know a lot of people greatly dislike the things Austen wrote, and I can understand that completely, but many aspects of what he did with Lorna really brought out storylines and potential that no prior writer was willing to bring back. Any time someone says "Austen's work was terrible," I always say that even the best writers have at least one bad thing they do, and even the worst ones have at least one or two good things, and I think Lorna's depiction in and of herself is one of those good things. Her time at that point, while "crazy," allowed her to demonstrate new and great uses of her powers, and more importantly, the Genoshan massacre and her suffering as a result of it did two things. One, it re-situated her with a greater focus on caring about what happens to mutants and their suffering, and two, the internal struggle between what fans would most easily see as the "Xavier" style and "Magneto" style of mutant-human relations came out in full force in Uncanny X-Men #443.
Uncanny X-Men #443 is what I consider to be one of her great issues, alongside X-Factor #243. It's hard for me to give a proper summary of that, but it does an excellent job of expressing Lorna as a character caught between two trains of thought, struggling with what's better in how to deal with humans, fear and a show of force or kindness and self-sacrifice. It harkens back to her very first issue where she's struggling with whether to fight alongside the X-Men or alongside Magneto.
Of course, M-Day happened, and her being one of Magneto's daughters led to Scarlet Witch depowering her, which allowed her to have some storylines where she had to try and figure out who she is and what her whole life means for her to no longer be a mutant anymore after all she's seen and done. That could've been the end for Lorna being a mutant, that could've been the point where she's left human and forgotten forever by Marvel, but the Genoshan massacre and other things she witnessed and experienced fed into higher stakes for her where she managed to get her powers back (and as a result of a major X-Men event where she became Pestilence).
I feel like I'm already over-loading with the text in my desire to share my thoughts on this, so I'll try to be briefer. There was a lack of storylines involving Lorna as one of Magneto's daughters for a while after her re-powering, but that tie did lead to some of the best stuff she's ever had: the AU version of her on Exiles, her meaningful role on the Wolverine and the X-Men cartoon, and the really amusing interactions she had with Crystal and Luna while she was in space. I also very, very strongly believe that if it wasn't for her being re-revealed as Magneto's daughter, then Lorna never would have received her origin story issue in X-Factor #243, something that took more than 40 years for her to receive while just about every character around as long as her got their origins told decades before.
I'm sorry for such a huge amount of text, but it's because I care about how Lorna as one of Magneto's daughters has done so much for her, provided her with things that she didn't get to have before, and all in just one decade. Right now, she's finally getting to lead her own team, the corporate-owned version of X-Factor, and while it's certainly possible she could have still ended up there with different circumstances, I sincerely think she only reached this point because of all the storylines that opened up for her by her association with Magneto as one of his daughters. There's still a ways to go for her, too. What I'm waiting and hoping for most of all is to see Lorna get to interact with Wanda. There is so much that can be done with them as sisters, currently the most high-profile sister relationship Marvel has. The company hasn't even begun to tap into its potential yet, it's been 5 years since they last did anything with it (Exiles), but interest in Lorna and Wanda's relationship as sisters is only growing every year.
With all the vastness of Lorna's untapped potential, every piece of it that is perfect and ready for use, I feel it means so much more for her to keep her status as one of Magneto's daughters intact to be explored than for her to lose it in the name of taking a cliche to task.
It wasn't just hinted it... her entire original storyline was based around the 1960s concept that she was his daughter and she was caught between following what her father wants her to do and following what she believes is best for her.
Then came the retcons including it being explained that wasn't really it was a robot.
Basically, that left Lorna with no underlying basis for thinking about who she is as a character or person other then her relationship with Havok and her powers. And, yes I liked as well in the 1990s the scenes where she questions why she is a super hero, if she is just half a couple with Havok, what is the status of their relationship, etc.?
But, currently the same oppruntiy exists for Lorna of questioning her place and introspecting and I have been a critic that she hasn't done enough of it at least since 2005, but that is a separate issue from her relationship with Magneto, Pietro, etc. Some of her best issues of all time were her dealing with physically and emotionally the fallout from the destruction of Genosha and the death of her father. They were good enough to end up being animated in the recent animated series WATXM.
But your point that we aren't allowed into Lorna's head the way we should of late to see how she views herself and the world I believe is quite apt.
I very much like her relationship to Magneto and Quicksilver, as well as Luna and Crystal. The only part of her family that she has yet to develop much of a relationship is with Wanda, but I see a lot of potential there as well.
Its given her a placement without totally defining her in the way some believe it does. She is on All New X-Factor right now with her half-brother Quicksilver and while their relationship somewhat defines their interaction, it more helps influence it.