My Fav is Trafalgar D. Water Law
I would say
Literally the best villain in the series bruh. He always ranks high in popularity polls
In terms of Straw Hats, Brook’s my favorite because of how his backstory presents him as this guy fighting to maintain what little sense of hope and spirit he has left even when all things seem lost. Pretty inspiring stuff.
But beyond that I feel like Robin might be one of the best written characters in the series because of her character arc - going from distrusting others who feels rejected in every turn to finally finding a family to trust who accepts her for who she is. And I love how overtime the Straw Hats personalities influence her to become much more livelier and quirky compared to her past self
Law is the Best :D