One great 'Bruce Wayne and Diana Prince Fanfic' is 'The Meeting of Titans'. It beautifully weaves their relationship, showing how their different personalities interact. The story has some really well - written action scenes where they fight side by side, and also some tender moments that make you root for their relationship.
Good fanfics in this category often play with the idea of their different values and how they can complement each other. Bruce is more about the gritty, street - level justice in Gotham, while Diana has a more global, myth - inspired view of justice. When a fanfic explores how these two views can merge or clash in interesting ways, it makes for a great read.
One great fanfic is 'The Father - Son Bond'. It beautifully explores the complex relationship between Bruce and Damian. It shows how Bruce tries to be a good father while also dealing with his role as Batman, and Damian's struggle to fit into this new world with his own strong - willed nature.
Another aspect could be that in some darker fanfics, if Bruce Wayne were to cross a moral line, perhaps Alfred would have to take more extreme measures. He might cut off Bruce's financial resources related to his vigilante activities. This would force Bruce to re - evaluate his actions and the way he operates as Batman. It's a way of punishing him to make him understand the importance of ethics even in his fight against crime.
He might develop a greater sense of humility. Without the Batman persona to fall back on, he has to face his own limitations as a person. For example, he may struggle to get people to listen to his ideas for change when he doesn't have the intimidation factor of Batman.
The plot is also important. It could involve them facing a new villain or a threat to Gotham that tests their relationship. Maybe a situation where Damian's actions put him at odds with Bruce's code of ethics, and they have to work through it. This kind of plot tension can make the fanfic really engaging.
A theme that is often explored is the clash of their worlds. Bruce is from Gotham, a dark and gritty place, while Diana comes from the idyllic Themyscira. Fanfics might look at how these two different backgrounds impact their relationship. For example, how Diana's more idealistic view of the world might conflict with Bruce's more cynical one, and how they overcome these differences.
I'm not sure if there is a specific 'Bruce Wayne lemon harem fanfic' available. There are countless fanfics out there, but a harem fanfic involving Bruce Wayne might not be as common as more traditional Batman - related fanfictions. You could try searching on specialized fanfic websites like Archive of Our Own or FanFiction.net.
A great idea for a Bruce Wayne training fanfic could be his training in stealth. He would practice moving silently through the shadows of Gotham. This could include training in different terrains, like the rooftops or the sewers.
In a fanfic, the family aspect could also include other characters. Maybe Bruce has a new family member that Terry has to protect, or there are family secrets that they both uncover. This could lead to a lot of drama and action. It could also show how Terry's own family views his role as Batman and how that affects his relationships at home.