I like Saavik's back story in the books, and I like the idea of movie continuity only Saavik ending up with Spock decades after the movies, but I am uncomfortable with combining the two -I.e. Saavik marrying someone who rescued her as a child and helped raise her since she was a girl.
I don't really see why. Such things unnerve us because of our awareness of sexual predators, but presumably such things are vanishingly rare among Vulcans -- and hopefully among 23rd/24th-century humans as well. And Saavik is not biologically related to Spock, so there's no logical reason for an incest taboo to apply. And by the time they marry, decades have passed since Saavik's childhood, and most of the time she and Spock have known each other, it's been as adults.
The version favored in the modern continuity (e.g.
Unspoken Truth) is that Saavik was raised as Sarek and Amanda's adoptive daughter, making Spock her adoptive brother rather than her father figure. That in itself can seem weird and incestuous, but there are precedents in fiction.
The Six Million Dollar Man and
The Bionic Woman established that Jaime Sommers, the love of Steve Austin's life, had been adopted by his biological parents after the death of her own (the adoption was apparently after Steve had left for college, but when they were engaged to be married years later, they were legally adoptive siblings). And similarly, on the current TV version of
The Flash, Barry Allen was in love with, and is possibly destined to marry, his adoptive sister Iris West. And in neither case is this treated as incestuous, because they aren't actually blood relatives. And neither are Spock and Saavik.