Perhaps there's a plot where Harry is trying to figure out who the mother of his child is, and it leads to a lot of drama and self - discovery. He might be in a love triangle or something similar that complicates the situation even more.
Another interesting plot could be Harry's journey in learning how to be a good father without much guidance. He could start from being completely clueless about taking care of a baby, like not knowing how to change diapers or feed properly, but gradually grows into a responsible and loving dad through various experiences and with the help of some friends or family members in the story.
There could be Harry's friends who play important roles. For example, his best friend might be supportive and help him out, or on the other hand, might be shocked and initially distance himself from Harry. And his family members, like his parents or siblings if they exist in this fanfic's universe, would also be significant characters. They could be either a source of support or create more problems for Harry depending on how the story is written.
One possible plotline could be how Harry and Ginny deal with the reactions of their friends and family. Their friends might be initially shocked but then come around to support them. Another could be their struggle to balance their studies at Hogwarts with the impending parenthood. For example, they might have to figure out how to manage their time between attending classes, doing homework and preparing for the baby.
One interesting plotline could be Harry's adventures in the afterlife realm where he has to deal with different types of souls. Maybe he meets some souls with unfinished business and tries to help them move on.
Well, one possible interesting plotline could be Harry teaming up with the Autobots to fight a common enemy. Maybe there's a powerful Decepticon that threatens both the wizarding world and the Autobots' home planet, and Harry's magic combined with the Autobots' technology is the key to victory.
Another plotline might involve Harry forming unique alliances with other druids. They could work together to protect an ancient druidic site from dark wizards who want to use its power for evil. This would lead to some exciting battles and magical duels.
Perhaps it focuses on his reasons for becoming a thief. It could be that he was forced into it by some difficult circumstances in his life. Like he was wrongly accused of something and had no way to prove his innocence, so he turned to stealing to survive and seek revenge.
One interesting plotline could be Harry's journey to master new paladin skills. For example, he might have to overcome challenges in a magical forest to find a rare weapon or spell that enhances his paladin abilities.
In 'harry is a king fanfic', a possible plotline is Harry having to deal with a rebellion. He would need to use his wits and leadership skills to quell it. Also, his love life might be intertwined with his role as king, like falling in love with a princess from another land which could have political implications.
One plotline could be Paul trying to protect his child from the dangers of the vampire - werewolf conflict in the Twilight world. He has to balance his role as a father and his duties as a werewolf.
Growth is also a major theme. Through the experience of becoming a father at a young age, these characters grow in ways they never expected. They become more mature, learn about sacrifice, and their understanding of love deepens. Their relationships with others, like their friends and romantic interests, also change as they adapt to their new role as a father.