I know that the Fletchling line learns Tailwind by level-up. However, when I tested it, only ONE parent (the Ducklett) knew tailwind. Both knew Roost. Fletchling can learn both Roost and Tailwind through level-up. Level-up moves are only passed down when BOTH parents know the move. Please correct me if I'm wrong or this has been changed in gen 6. My understanding of the breeding mechanics may not be as clear as they were a few months ago, but I don't believe that I've forgotten everything, even with all the new changes in gen 6. Practically the only thing I did in gen 5 was egg abuse.
Anyway, Night Slash and (rather obviously) Heart Stamp are NOT egg moves. I don't quite remember for certain, but Agility is also part of the no-go list.