People calling Luffy "pathetic", seem to forget that he is a 19 year old teenager with funny hormones. Give him a 2 arcs or few, he is going to defeat Imu and become the strongest being in the world. For simple comparison Zoro, at the same age, had even not yet started his journey.
Ace and Sabo: prodigy level 1
Zoro and Sanji: prodigy level 2
Luffy and Coby: prodigy level 3
All six guys are much stronger than anyone else at the same age, but they're not where they need to be just yet. Luffy by even the age of Law, who's also much younger than most, should beat Imu quite cleanly



