A great plot twist might be that Po discovers he has some hidden connection to Tai Lung. For example, they could be related in some long - lost family way. This would add a whole new layer to their relationship and the story. Po would then have to grapple with the idea of fighting someone who is, in a way, family, and Tai Lung could use this knowledge to his advantage in different ways during their confrontations.
One common theme could be the exploration of their relationship in a more romantic or complex way. Since they are from different sides in the Kung Fu Panda universe, there might be themes of redemption and understanding in the fanfiction.
A frequent theme is the power dynamic between them. Given Tai Lung's great strength and his fall from grace, and Tigress's own position in the Furious Five. Fanfictions might play with the idea of who is more powerful in different situations. There could be themes of respect as well. They might initially not respect each other, but through various encounters, they come to respect the other's skills. Also, themes of loyalty can be explored, especially when they are faced with challenges that test where their loyalties truly lie, whether it's to their own beliefs or to the people around them.
I'm not sure about specific 'tigress and tai lung lemon fanfiction' as it might be a rather niche area. However, you could try searching on fanfiction - specific websites like Archive of Our Own or FanFiction.net. They usually have a wide variety of fan - made stories.
One possible plotline could be that Tai Lung, after his defeat, somehow gets a chance at redemption. Tigress, seeing his change, starts to develop feelings for him. They could start training together secretly, and as they spar, their mutual respect turns into love. Maybe they work together to protect the Valley of Peace from a new threat, which brings them closer.
For Tai Lung, in fanfictions, his character could be developed by exploring his backstory more deeply. Maybe there were events in his childhood that made him so desperate for the Dragon Scroll. This could make readers sympathize with him more. Tigress could be developed in terms of her relationships with other characters. For example, how her relationship with Tai Lung affects her relationship with the Furious Five. She might become more independent from the group as she spends more time with Tai Lung. And Tai Lung could be developed to be more adaptable. He could learn new ways of thinking and being from Tigress, and Tigress could learn to be more assertive from Tai Lung's boldness.
In the 'rwby tai vs raven fanfic', it might focus on the backstories that led them to this point of conflict. Tai might be fighting for the sake of his family or his ideals about protecting Remnant. Raven, on the other hand, could be in the fight for her own self - interest or to protect secrets she holds. The fanfic could also show how their relationship, whether it was once friendly or always strained, affects the way they fight each other.
Tigress is very reserved, while Tai Lung was quite bold in his actions. In a relationship, Tai Lung might be the one to make the first moves, which could initially make Tigress uncomfortable. However, as time passes, his boldness could break down her walls. On the other hand, Tigress's reserve would force Tai Lung to be more patient and understanding, which would be good for his character development.
Well, if Tai Lung was injured and Po found him instead of fighting him right away. Po could take Tai Lung to the Jade Palace and nurse him back to health. During this time, they would have conversations and Tai Lung would see the kindness in Po and the true meaning of the kung fu that he once coveted. This would change their relationship from one of enmity to one of mutual respect and a strange kind of friendship.
Perhaps a plot twist would be that during the fight, Tai discovers a secret about Raven that completely changes his perception of her. For example, he finds out that she has been working undercover to stop a greater threat all along, and their fight then turns into a reluctant alliance against a common enemy.