One common theme is honor. Orcs are often depicted as having a strict code of honor within their clans. Another theme is struggle, like their fight for survival in a harsh world. Also, loyalty to their tribe or comrades is frequently explored.
Sure. Some stories tell of an elf princess making friends with different creatures in the forest. She learns about their cultures and helps them in times of need, which is a great positive and family - friendly story.
One common theme could be the clash of different cultures. The elf culture from the princess's side and the ninja culture in Naruto. Another theme might be friendship. Maybe the elf princess forms strong bonds with Naruto and his friends.
Well, 'The Orcish Rebellion' is a notable fanfiction in this variety. It shows how the orcs rise up against an unjust power in their fictional world. There's also 'Orcish Love in the Time of War' which, despite the title, is more about the bonds of loyalty and friendship among orcs during a difficult time, rather than just a love story.
Well, usually in manga, to become a princess, you need to have kindness, courage, and a heart full of love. Also, a bit of luck and some magical elements might help.