She always tries to be a good person and do the right thing, but her life gets ruined in almost every timeline, and through no fault of her own.
The only exception I can think of is the Zeal timeline, in which Ocean Palace Lavos is defeated. In that case, Zeal never falls, the malignant influence of Lavos is ended so the Queen goes back to normal, and the Zealians are forced to revert to elemental power and a more sustainable lifestyle. However, this is not canon and it's highly unlikely.
I've probably said it already, but the merging/reincarnation angle never sat well with me.
Thankfully, the fact that multiple realities can technically exist helps take the sting out of the whole thing. With the Time Devourer technically ceasing two exist, Schala would probably be whisked straight to 1000 AD in stead of the gap between dimensions. From that point, there are at least two outcomes for future timelines:
1. One where Schala's prayers are heard by the Frozen Flame before she's whisked out of the Ocean Palace and she reincarnates into Kid mid-transit.
2. One where Schala is whisked away before the Frozen Flame can grant her prayers, and she arrives in 1000 AD as herself.
The first option may ultimately be the kinder one, as she'll have a life unrelated to her old one, gaining the necessary life experience that will ease the transition of her eventual returning memories.
The second one would be far more difficult for her, as she would end up living with the knowledge that the blood of her kingdom is technically on her hands without the emotional buffer of reincarnation.
We've seen in Radical Dreamers how the former would eventually resolve However, I feel the latter would have more of a payoff as Schala learns to accept the past and eventually learns (the hard way) how to forgive herself and seek her own happiness, and I hope they go this route in a future game or story.
...of course, one could always just ignore the above and go the fanfiction route.
*cough*shamelessselfpromotion*cough*