Well Jacen got a topic... lets not forget his sister. I think there is something special about Jaina that even many authors either did not get or ignored sadly. Something that goes right back to her inception and name. JAINA Solo, whose name meaning would be equivalent to Victoria/Victor, no doubt is a winner. But aside the obvious translation, her name being derived from the religion of Jainism in India, her fate could not have strived further from her titular named purpose and connection to that ancient tradition of non-violence. In that regard lets try to resolve the discrepancy between Jaina Solo as portrayed, as intended and as reconsiled much like the Jacen topic tried to do with him. Whereas Jacen derived from Jason, means "Healer", something befitting his talent with animals and people and his intended life's goal, to seek out all that is separated, learn all he can and heal and reunite the fragments of Force Cults, lore and galaxy into one cohesive unified new view. Now, Jaina will be victorious with whatever she sets her mind to. But her name reeks Jainism's nonviolence, a very Jedi virtue. She never was the lightsaber-happy warrior her brother as a kid wanted to be. She rather loved machinery and tinkering, aka figuring out problems and solving them. Seeing how things work and finding what makes them spin and working with that. A talent easily applied to life, nature and not just machinery even to resolve conflict in a nonviolent way. In that regard Jaina and Jacen as twins really worked well together, both approaching the same problem from different angles but towards the same resolution. Jaina from the inside, working out the mechanisms and levers to pull, Jacen from the outside, understanding context and surroundings and healing by realigning what had gotten out of synch with balance and harmony. Now we know fate threw a lot at them, separated them, pitched them against each other... Jaina became a pilot, warrior, a Sword and Buffy the Sith Slayer... her own dark side trips went rather unhealed and sanctioned by the Jedi Council sadly. Is this a betrayal of her name and Jainism? Or is this a growing process of Jaina coming to terms with herself and ultimately rejecting violence to become a better Jedi, a Sword of the Jedi that needs no blade or to cut to win. We saw Jaina free slaves and be a mediator in FOTJ. We saw her not much so far as part of the Felpire and at Jagged's side changing it from within, as well as ultimately rebirthing a new kind of Imperial Knight Order. We saw her not yet but she probably will be working with the Imperial Mission in the future. Is this a redeemed Jaina, a changed Sword of the Jedi? As a pilot, Jaina was a warrior that just needed a target and a trigger. No wonder fate quickly separated her from that as the Force had other purpose for her. Regardless if she flew often enough in her own squadron later on, regardless if she tried to resist that fate, she was pushed always towards certain events and actions that needed her specific talents. Be that with the Vong, on Hapes helping Tenel Ka, later helping Tahiri cope and reunify with Riina Kwaad, etc. In a way it is poetic... if one looks beyond the sadness: Anakin died a hero, Jacen died a villain, and yet in life and death, twinbonds and dyads are more than the sum of their parts ever after still. Tahiri has lost Anakin and has dived through her own grief, loss and dark side to become a stronger person able to maybe reunite with Anakin from beyond the grave and accept that. Jacen has reminded Jaina of her Darkness for in his death he tried to save Tenel Ka and Allana and only later Jaina would realize or understand her lost brother better I hope. Maybe when taking Allana as her Padawan one day, like Mara had trained her. With the right teachers Allana can become a synthesis between Jaina, Jacen, Tenel Ka, maybe Tahiri and Anakin too. Will Jaina see the error in her warrior ways and reject them? Will she become the nonviolence preaching Jainist warrior of Peace? "Victory without War", the slogan of the Imperial program and Imperial Mission scream that as much as it could be a literal translation of her name! It was a long violent road, but like everybody else she suffered, erred and changed to become what her name meant from the very beginning.
Was Jaina actually named in inspiration from Jainism intentionally? (Jaina itself is not a common name that I know of in RL). It’s an interesting write up, and Jaina’s story ending in FOTJ as it does and her later role does fit pretty well with what your thesis is. If there is any part where I disagree-it’s that Jaina’s “inner darkness” as a concept is only really brought up in dark journey and maybe a little bit elsewhere, Jaina is simply not a main character the way her brother is. So her internal conflicts aren’t really seen. It does make one wonder how a jacen/Jaina duo if Jacen had not fallen would have looked. Because as you note, they actually do complement each other in some rather profound ways.
Don`t think so, I think Jacen was named after the newborn son of a friend of Zahn while he wrote TTT, and then Jaina was picked for the same twin naming convention as Luke and Leia.