The predominant surviving forms of new SF are tv/movie tieins, and military SF. Of the remainder of new SF books an increasing proportion are YA. Now, YA is not a well defined genre, but the expectation that there is a young lead character for younger readers to identify with in their quest to find their place in the adult world. This has always been a major element of science fiction, from Andre Norton and Robert Heinelin down to the lowly superhero comic.
A reasonably success entry in the YA SF genre is Paul Melko's The Walls of the Universe. The book is a fixup of a successful novella. It is still left incomplete in one sense. What will ultimately happen and why the hero is chose for his bizarre fate is left for a book series. Serialization will probably decompensate what good has been done, but the demands of commerce must still be met. That good done is an interesting exercise in adolescent roleplaying, literalized as the same person from different parallel universes.
One is a typical good guy, of geekish persuasion, but notably successful in attracting not one but two women to love him, which takes the curse off being smart. Plus he seriously humiliates the real physics geek. And he rises to the occasion when battle is forced upon him, and kills the enemy.
The other is a modern day Magnificent Bastard, who is a murderer, in self defense of course so he's not really a true murderer. And the victim is a psycho who torturers animals for fun. And although he screws lots of his predestined girl friends in parallel world after parallel world, so that he's callous horny dog, he is a remarkably successful horny dog, which really soothes the sting, don't you know?
Both become tycoons at an early age by use of their knowledge of parallel worlds. The gadget making all this possible wrinkles the plot by only working one way. Geek version reverse engineers the gadget so that the plot is successfully resolved by returning to previous universes. Together, they kill numerous bad guys, get rich, get the predestined girl, as well as the adoration of assorted parents, even the parallel world version who didn't give birth to the protagonist! There's nothing quite so predetermined as the other characters' love for the hero, no matter what world they come from.
Putting aside all the plot huggermugger, the basic story is this: An adolescent, choosing what kind of man he will be chooses to be a badass, but eventually realizes that he needs love and reestablishes family relationships and a nonexploitative relationship. The adolescent also get to be the goody two shoes, who must leave home to grow up, never coming back, and finally becoming a man by killing. This is all literalized by the bad ass conniving to send the nice guy on a one way trip with the sabotaged transport device, which he himself received from another parallel world version of himself. (Presumably infinite regress means Melko can milk this till he dies.) So the adolescent reader can be both.
But, in the end, the very best conventions of the CW triumph, with twenty somethings Lords of the Manor, worldweary and beset with cares but still smoking hot. Bad ass literally gets away with "murder," by replacing the victim with a parallel world copy. Forging a corpus non delecti is a novel twist. There is a general flabbiness due to the wish fulfillment, and a bitter undertaste due the underdeveloped moral world created. The contrast between the modern notion of a hero and the older notion of a hero however is much more honest than the ruck of YA stories I've seen of late. Recommended, but approach with modest expectations.