Sex and spaceship battles? The one which immediately leaps to mind is Richard Lupoff's "With the Bentfin Boomer Boys on Little Old New Alabama", which was published originally in Harlan Ellison's anthology, Again, Dangerous Visions (it was later expanded into the novel Space War Blues).
On the general topic of such things, you might want to look up the writings of some of the other New Wave (both British and American) from the 1960s, who pretty much finally shattered the taboo on sex in science fiction....