Bob Swindells may advise ending a story in a way that surprises the reader but still feels logical within the context of the plot. It could also involve resolving character arcs in a meaningful way.
Well, it really depends on different fan preferences. Some might like a Connor who is a powerful fighter with unique semblance skills. For example, a Connor who can manipulate time in some way, like slowing it down during battles. This kind of characterization often makes for exciting action scenes in the RWBY fanfiction world.
It could be an older, more experienced android. One that has been through a lot and has a deep understanding of both the android world and human society.
Hank would be a very likely character. He already has a complex relationship with Connor in the original story. If Connor starts to become deviant, Hank's reaction could be very interesting. He might be suspicious at first, but then as he sees the positive changes in Connor, he could support him.
One common plotline is Connor joining the Beacon Academy. He has to go through the initiation process, just like Ruby and her friends. He might struggle with the physical tests or have an interesting interaction with Professor Ozpin during the interview. For example, Ozpin might sense something special about Connor that sets him apart from other students.
Superman can use his super - speed to quickly move Connor away from any danger. For example, if a villain attacks, he can grab Connor and be miles away in an instant.
A new villain could be introduced in the fanfic who is specifically out to get Connor Kenway. This villain might have a personal grudge against Connor or be on a mission to eliminate all the Assassins, and Connor becomes their prime target and ultimately falls to their schemes.
There are quite a few. 'Connor's Trust' is a fanfic that focuses on how the reader earns Connor's trust in the Detroit universe. It has some really interesting character interactions. 'Love in Detroit' is a more romantic take on the Connor/Reader relationship. It shows how love can bloom even in a post - apocalyptic Detroit. Also, 'Allies in Detroit' is a story about the reader and Connor becoming strong allies, facing all the challenges Detroit has to offer together.