Maybe they could combine Naruto's Rasengan with Bakugo's explosive power. Picture Naruto forming a Rasengan in his hand and Bakugo adding his explosive energy to it, creating an even more destructive and concentrated attack. This would be a really cool combination in a fanfic.
One idea for a Naruto vs Todoroki fanfic could be that they are brought into a strange new dimension by some sort of magical entity. Naruto starts off with his usual energetic self, trying to figure out what's going on. Todoroki, on the other hand, is more cautious. Naruto might start with a simple Rasengan attack, but Todoroki uses his ice side to block it. As the battle progresses, Naruto realizes he needs to up his game and taps into his Nine - Tails chakra. Todoroki then decides to combine his ice and fire powers in an attempt to counter Naruto's new - found strength.
The most exciting scenario would be when Naruto goes full Nine - Tails mode and Todoroki uses his maximum ice and fire combination. Naruto in Nine - Tails mode is extremely powerful, with his chakra radiating and his physical abilities enhanced. Todoroki, when he combines his ice and fire, can create a powerful and unpredictable force. The clash between Naruto's brute strength and Todoroki's elemental control would be visually stunning and full of intense action. The environment around them would be completely transformed, with the ice melting and the ground shaking from Naruto's power.
One interesting plotline could be Deku having to face off against his classmates in a series of challenges that test not only their quirks but also their teamwork and strategic thinking. Maybe there's a misunderstanding that leads to the conflict.
One common theme is rivalry. Bakugo's aggressive and competitive nature against Todoroki's more reserved yet powerful self makes for an interesting dynamic. Another theme is friendship development, as they often start off at odds but then find common ground.
In some fanfictions, Bakugo can become more empathetic. For example, if he experiences a situation where he realizes the pain he's caused Deku over the years. His aggressive nature might soften as he starts to understand Deku better. Deku, on the other hand, could become more assertive. Instead of always being the timid one, he might stand up to Bakugo more firmly in fanfiction scenarios.