There are many great writers out there. Some popular ones are often those who are really good at capturing the personalities of Spencer and Toby as they were in the show. For example, some writers on fanfiction.net have a large following for their PLL fanfics. But it's really subjective, as different people like different writing styles.
Well, it's hard to say who the 'best' is as it depends on personal taste. But some popular authors might include those who have a deep understanding of the characters. For example, some authors who have been writing for a long time and have a large following. They are often good at capturing Spencer's intelligence and Toby's more reserved nature.
One interesting storyline could be their future together. Maybe they move away from Rosewood and start a new life, away from all the drama. They could be building a house and planning their wedding at the same time.
One interesting storyline could be them solving a mystery together that is separate from the main 'A' plot in the show. They use their combined intelligence and Toby's skills to uncover something that has been hidden in Rosewood for years.
A really interesting plot could be set in an alternate universe where Toby is a detective and Spencer is a journalist. They team up to investigate a series of strange disappearances in their town. As they dig deeper, they start to realize that there are forces at work that are much bigger than they initially thought. Their relationship evolves from professional partners to something more romantic as they face danger together.
In the Pretty Little Liars universe, Toby and Spencer are from different worlds in a way. Toby has his own troubled past, and Spencer is from a more privileged background. When they come together, it creates a lot of tension and chemistry. Fanfiction can play with this dynamic, showing how they overcome their differences. Also, their love - hate relationship at times in the show gives fanfiction writers a lot to work with. For example, they can write about how their arguments turn into passionate reconciliations.
One of the best elements is the exploration of their complex characters. In fanfiction, we can see different sides of Emily and Toby that might not have been fully explored in the show. For example, we can see how Toby's troubled past affects his relationship with Emily on a deeper level.
One key element is the character interaction. How Spencer, with her intelligence and complex personality, interacts with Dean, who likely has his own set of skills and traits. Another is the setting integration. Incorporating the dark and mysterious world of Pretty Little Liars with Dean's possible role in it. Maybe he could be helping to uncover the 'A' mystery or dealing with the other secrets in Rosewood.
Another aspect in fanfiction could be a romantic relationship between them. Their personalities, which are both strong and independent, can create a very passionate and intense dynamic. Writers might explore how they deal with their feelings in a world full of secrets like in Pretty Little Liars.
One common theme is mystery. Since the show itself is full of mystery, fanfictions often continue this trend. Spencer and Alex might be involved in solving a new mystery together, perhaps related to their families or the town's secrets.