If I wrote X-Men I would do a Summers family in space 12 issue run where Cyclops and family [Jean, Cable, Hope, Rachel, Havok, Madelyne and even Lorna and Wolverine tag along for drama because of course] are visiting the Shiar Empire and suddenly they find themselves in the middle of a coop against Xandra and Vulcan is freed from his Arrako prison by a mysterious figure who is some kind of Shiar superguardian black ops operative [Like the ones that murdered the greys][Which we later find out was a deed actually masterminded by this figure]. This figure has some pretty serious powers that I can't determine the exact nature of yet but something omega level like vulcan except affecting mental and psychic energy as well. Her look would be reminiscent of despara in motu complete with cape and everything.
Anyway this figure which is clearly female and humanoid in appearance somehow knows about Vulcan and has a huge grudge against both Lilandras family and the Summers family, especially Corsair. She finally makes her move after years of being in the shadows and challenges the praetor for leadership of the imperial guard and is able to remove his confidence [part of her powers] and easily beats him. And she installs Vulcan as the emperor and somehow has control over him and he does everything she says. Her powers make it easy to control him... but is it just the powers at work? The story plays just like Deadly Genesis in that we slowly start to unravel the mystery of who this is and if you haven't figured it out by now it turns out to be Katherine Summers who it turns out was a very powerful mutant who hid her powers from her husband and was in denial of them and wanted a normal life and the Shiar attacked her craft because they homed in on her very powerful mutant energy signature. Once discovered she was pregnant they kept vulcan around to harness that power. You also notice that Vulcan is significantly more powerful than Scott and Alex and it is because their powers have not been enhanced by her presence [part of her powers] so we get to power up these two dudes significantly after meeting their mother again. They found out she has gone mad from surviving having her son taken from her belly and left for dead only to be saved by fellow slaves. And then discovering her sons were alive, and Corsair had not rescued her, etc etc. Part of her power is to remove peoples courage and mental energy and she essentially scared Corsair away from her this whole time. Or did he freak out when he realised she was a mutant? Something to add to the fire. In the end the story serves to tell the story of what happened to the Summers bros mom and where their crazy genetic potential comes from. Which weve been led to believe came from the Summers and the manipulation of Mr. Sinister. And as it turns out, he was in on the Katherine Summers thing too. So much so that he had her in the same orphanage that he later had her son in. She also saves Scotts life at some point and tries to bring him over. I don't know. My 2 cents worth of fan fiction for the day. In the end she is presumed dead. The summers bros develop stronger versions of their powers and in cyclops case full control of his beams as well as the nature of what the beams actually are. I may even give him super strength.