Blue is my favorite, from a gameplay standpoint his team can be silly and underwhelming, but the character is timeless.
Silver is very good too, his character growth is genuinely interesting and the expanded story / interactions in HGSS definitely shoot him up to top two.
Top three I'd say goes to Hau, he sort of represents the pinnacle of nu-trainer archetypes. He's supportive, happy, always excited for the next path in his journey (in doing so, gets you "pumped" too) and has moments of self-doubt, but realizes what he needs to do. He's so pure and friendly, there's really no way you can hate the little guy unless you... Well... Hate him. Also his team in USUM almost fucked me up.
From here it gets a little muddy and underwhelming, but i'd say-
4) May/Brendan >I think it's funny how they're self-admitting shitty trainers in the story, but will fuck you up if you're slacking.
5) Shauna >she's cute and checks up on you more than others. I don't really have a hate boner for the XY characters like most people and this game was there for me when I was in a rough patch
6) Hugh >Having a villain-centric story relevant to the rival was fresh, and he definitely the closest we've had to a more pissy, hardass rival since the Game Boy era. Unfortunately his character arc ties up in a very weak way, somewhat disappointing.
7) Tierno + Trevor + Serena/Calem >Contrary to what many people think, I enjoyed the pseudo "you have friends adventuring with you" concept that XY tried. They're very simply characters but oddly satisfying in that way. Tierno likes to dance I respect that, and it's kind of hilarious how his team has nothing to do with it. Trevor has a good design, and I would grind Serena/Calem's team every day in post-game.
8) Gladion >Very underwhelming. I think he's a victim of too many characters in Alola.
9) Cheren/Bianca >Meh
10) Wally/Trace >Very meh
11) Barry >I honestly don't remember anything about him.
