She was likely very beautiful, as elves are generally described as such in Tolkien's works. Her beauty would have been both physical and in her grace and elegance.
She may be creative. For example, in the story, she might be very creative in decorating their home in a unique Japanese style. She could use traditional elements like tatami mats and shoji screens in innovative ways. Also, she might be empathetic. She can easily understand the feelings of others in the family. When her children are sad, she is quick to comfort them and offer solutions.
One possible plotline could be little Thranduil learning important lessons from his father Oropher about leadership. For example, Oropher might take Thranduil on a hunting trip in the forest and teach him how to read the signs of the land, which is a valuable skill for a future leader. Another could be Thranduil getting into trouble while exploring on his own and Oropher having to rescue him, which would strengthen their bond. Or perhaps a story where Oropher tells Thranduil tales of their ancestors, passing on their family's history and values.
It could be that there was some sort of magic involved. Maybe an enemy of Thranduil cast a spell that made the dragon more aggressive towards him. The dragon fire might have some special properties due to this magic, and Thranduil's burns could be not just physical but also have some sort of curse or negative effect on his being. He then has to find a way to break the curse while dealing with his injuries.
One common theme is the anticipation and excitement in the elven community. Since elves have a long lifespan, the birth of a new heir is a very significant event. Another theme could be the relationship between Thranduil and his wife getting stronger as they await the new addition to their family. For example, in many fanfics, Thranduil becomes more protective and loving towards his wife during this time.
In J.R.R. Tolkien's lore, Thranduil's wife is not really detailed in the main stories. However, in some fan - made stories, she might be depicted as a very elegant and strong elleth. She would have been by Thranduil's side during the early days of his rule, sharing in the joys and sorrows of building and protecting their realm. She might have been a great support in matters of diplomacy and in handling the internal affairs of the Woodland Realm, but all of this is just speculation based on what we know about the general nature of elven society.
One positive trait is loyalty. A good wife is loyal to her husband and family, which creates a stable family environment. For example, she will stay by her husband's side during tough times like financial difficulties or health problems.
One positive trait of an older wife is her maturity. She has likely been through more in life and thus can handle difficult situations with more calmness and wisdom. For instance, in a family argument, she may be able to mediate and find solutions more effectively than someone with less life experience.
In a story, a wife can have many positive traits. One is loyalty. For instance, she stays by her husband's side through thick and thin, like in times of financial difficulties or health problems. Another trait could be her kindness. She might be the one who volunteers in the community and shows compassion to those in need, which also reflects well on her family.
Very little is known from the official sources. She is mostly a mystery.
One short story could be about a wife who is extremely kind. For example, she always volunteers at the local shelter, taking care of stray animals. Another story might be of a wife who is very intelligent and uses her knowledge to help her husband start a new business. She does all the market research and comes up with innovative ideas.