One plot development could be Ruby influencing the training of her team. Knowing what challenges they will face in the future, she could make their training more effective. For instance, she could push Yang to work on her anger management more seriously as she realizes how it can be a weakness. Ruby could also try to form alliances with other groups earlier. By going back in time, she has the chance to rewrite the events in a way that gives her side more advantages in the long run.
In this fanfiction, Ruby might go back in time and try to save Pyrrha. Since she knows what's going to happen to Pyrrha in the future, she could take actions to keep her alive. This would have a huge impact on the story as Pyrrha was a very important character. Ruby could also try to expose the villains' plans earlier, thus changing the whole course of the battle against them. She might also use her time - traveling knowledge to get better weapons or resources for her team.
Well, one possible plot development could be Ruby using her knowledge of future events to prevent certain tragedies. For example, she might stop the fall of Beacon earlier than it originally happened. Another could be her trying to change the relationships between the characters for the better. Maybe she'd make sure Weiss and Blake become friends more quickly. Also, she could work on improving her own skills faster by learning from her past mistakes.
One possible plot development could be Ruby struggling with her self - confidence. Losing an eye would change her perception of herself as a huntress. She might have to relearn how to fight and be more cautious. Another aspect could be the reactions of her team. Weiss might be overly protective, Blake could be empathetic due to her own past traumas, and Yang would be angry and determined to find out who or what caused it. The story could also explore how Ruby's Semblance is affected. Maybe it becomes less stable or she has to learn new ways to control it with her reduced vision.
For Whitley, he could start off as a cold and aloof character, but through his interactions with Ruby, he could become more empathetic and caring. Maybe he realizes that there's more to life than just status and wealth. For Ruby, she could learn to be more patient with people like Whitley who come from a different background. She might also develop a better understanding of the complex social structures in Atlas.
Well, perhaps Gohan goes back in time to save his father, Goku, from some early danger. He could then train alongside Goku when they were younger, leading to a much stronger Goku earlier in the timeline. This could also have a ripple effect on the relationships within the Z - fighters. For example, with a stronger Goku earlier, their battles against the Red Ribbon Army or other villains might be much easier and quicker.
There's a possibility that a new character could emerge as the main antagonist. Ruby's time - traveling could disrupt the normal flow of events, and this might create a new power - hungry or revenge - seeking character. This new antagonist could be someone who blames Ruby for the changes in the timeline and wants to stop her at all costs.
A possible plot development is that Ruby's amnesia could be a result of some dark magic or a new type of Grimm attack. As she tries to recover her memories, she discovers new powers within herself that she didn't know existed before. This new power could be related to her amnesia in some way, like it was locked away and the amnesia event somehow unlocked it. Meanwhile, her friends are on a quest to find a way to reverse her amnesia, which leads them to encounter new allies and enemies along the way.
One common plot development could be that Harry tries to prevent the events that led to his death in the first place. For example, he might focus on changing how he dealt with Voldemort. Another could be that he uses his knowledge of the future to form different relationships. He may be more cautious with some people and more open with others. He could also try to save the lives of those who died before, like Sirius or Dumbledore.
Maybe the spider bite is venomous, and Ruby has to struggle with her health deteriorating. As she battles this, she discovers that the venom has a connection to an ancient Grimm or some other dark force. She then has to go on a journey to find the antidote, which might be hidden in a dangerous and unknown place. Along the way, she might meet new allies who have had similar experiences with the spider - related things. And these new allies could teach her how to better manage her situation until she can be fully cured.
One possible plot twist could be that when they go back in time, they accidentally change something that has a huge impact on their future relationships. For example, Naruto might unknowingly prevent Sasuke from leaving the village in the past, which could completely change how they interact in the present they return to. Another could be that they find out a hidden truth about their parents or the village's past that was covered up, like a secret alliance that their predecessors were involved in.
One interesting plot could be that Harry uses his knowledge of the future to help Snape avoid some of the bullying he endured. For example, he might warn Snape about certain Slytherins who would target him. Another could be that they work together to change some small events that have a big impact on the overall wizarding world's future. Harry might also introduce Snape to some of his future friends in a different context, like showing Hermione's intelligence to Snape much earlier.
A really interesting plot twist could be that Steven goes back in time and discovers that the Diamonds had different motives than he originally thought. Maybe they were being influenced by some other force in the past, and by going back, he uncovers this mystery. Also, he could find out that some of the things he thought were his friends' ideas were actually planted by an outside source long ago. This would completely change his understanding of the relationships and history in the Steven Universe world.