We have seen a lot of rivals throughout the series. But which rival do you think is more interesting in terms of their personality and influence. For this, let me list a few I remember.
Spoiler:- A few Rivals:
Gary. He was always with the ladies. He is Ash's childhood rival, and he beats him at everything, which pushes Ash to the top. But in Johto and at the gym battle against Giovanni, Ash proves him wrong. When Pidgeotto beat Rhydon by Double Edge, that was completely unbelievable and even no Pokemon would do domething like this. Gary chose to give up his training job and chose to be Ash 's friend, as he becomes nice to him. He's not much of a stereotype.
Ritche, a somewhat equivalent copy of Ash. He seems very nice and his character is good, though some of the types of Pokemon he owns is freaking similar. And he won in the Pokemon League since Charizard sleeps on his own, not obeying Ash. But he's a lot less like Ash personality wise.
Paul, OMG. This is like Gary, though he is from Veilstone, he travels the same regions Ash did, and he is strict when it comes to battling. He is right in terms, as I get to feel in his determination of being tough, like when he chooses to be tougher than his brother. But he is downright rude, even to Chimchar. You knew that it has potential, but you aren't giving Chimchar the right treatment. Ash has done a good job with doing something you never did, and it is to trust in your Pokemon and care for them.
Trip, I have nothing to comment on. He's like the rest, but it's surprising that his Snivy defeated Pikachu. But Pikachu could have defeated Snivy with Iron Tail. But he is a strong willed trainer who is tough.