It could be Captain America. He has a strong sense of justice and kindness. So, if he found a dog, he would surely take it under his wing and protect it. Maybe he'd even train the dog to be a mascot for the Avengers.
In some fanfictions, the 7th Avenger could be a time - traveler from the future. This person has come back to prevent a major disaster that the Avengers couldn't handle without their help. They know all about the future events and use this knowledge to guide the team, but also have to be careful not to change the timeline too much.
Iron Man is often a popular character in avenger time travel fanfic. His intelligence and technological prowess make him a key player in any time - travel scenarios. He can figure out the mechanics of time travel devices and come up with strategies to fix problems in the timeline.
One interesting concept could be the Avengers going back in time to prevent certain events that led to major disasters. For example, they might go back to stop Loki from getting the Tesseract in the first place. This would change the entire timeline and create a whole new set of adventures and challenges for the team.
Maybe Harry could use some of his magic skills to assist the Avengers in a battle against a powerful enemy. For example, he could use a spell to freeze the bad guys momentarily while the Avengers strike.
Well, it combines two really exciting concepts. The Avengers are already super popular, and time travel adds this whole new layer of mystery and adventure. You get to see different versions of the characters, like what if Iron Man met his younger self? And the reader being part of it makes it more immersive, as if you're actually there in the Marvel universe traveling through time.
Percy could also be a big fan of Hulk. Just like Percy has his own 'inner beast' that he sometimes has to control (his demigod powers), Hulk has his own anger issues. Percy might see a bit of himself in Hulk and also be in awe of Hulk's raw strength. He would probably be interested in seeing if there's a way to help Hulk better control his rage, using his own experiences of self - control.
There have been many suspects over the years. One theory pointed to a person with a connection to the seedy underbelly of Hollywood at that time. This person might have been involved in illegal activities and had a disturbed mind. But without conclusive evidence, it's all speculation. The case is complex as there were many people who could have had motives, including those who knew the victim Elizabeth Short on a personal or professional level.
Yes, perhaps in this fanfiction Bella could be a new Avenger. Fanfictions often introduce new characters or give existing characters new roles within the established Avengers universe.