I think there was a hand on the cover which looked like it was pushing through/covered by a type of material. The last or near-last story was about a girl and boy with powers who'd been raised on a spaceship (?) and they weren't allowed to be together as they had higher purpose. Right at the end, during a final struggle with the people who raised them and are trying to keep them apart, he tells her to let time spin or something like that, as a form of possible annihilation or escape? Any ideas would be really helpful, it's been haunting me for well over a decade!
I think the author was a man. I think it definitely was more on the young adult side of writing. The title of the collection of short stories/the book could have been one word. The couple in the last story I'm referring to were raised by these people who tried to keep them apart/stop them falling in love and, I think, were slightly scared of their powers.