Blue - From a personality stand point I love his attitude. He is the first and only rival too become champ which I would like to see a return to that dynamic. He has a well balanced team which I like to see from a Champ. His teams as a Champ and Gym Leader are just as good as anime champ imo.
Red - His team is alright but not the best. Woo all starters, Snorlax, Pikachu, Lapras/Espeon. Not bad but the preference is blue since like in the anime all starters are just too generic. But again he doesn't revolve around one type like other champs.
Lance - Seriously three Dragonite at times... Or Dragonair. I want a Champ that doesn't share the same species as one another. Or too be at a point where his pokemon isn't fully evolved(although not as a Champion). On top of this he is one of the champs that is a specialist, for me I want a Champ with variety.
Steven - Although he "supposedly" specializes in Steel types he has two fossils and Claydol, that's hardly specializing in one type when half his team is only Steel. Too me Steven is middle of the road for all the champs. I like his team like Metagross, Skarmory, Aggron, Armaldo. I think it would have been bettered to make him more of a specialist in it maybe give him another steel like Steelix. All in all not overly impressed.
Wallace - Probably my least favorite Champ, not only cause his team isn't really that great to me, but also he specializes in Water which I am not really a bad fan of that typing. Nor pokes on his team like Tentacruel(shoot see enough of these while surfing), Whiscash(awesome typing, but too me it would have been neat if they have Swampert instead). Gyarados and Milotic are good stuff though (=.
Cynthia - She is just a notch above Blue and Red too me. She has the best typing mix 5 out of her 6 pokemon being dual typed. Garchomp and Lucario alone are badass. They did a great job replacing Gastrodon with Togekiss. It already made a excellent team even better. She is definitely involved through out the storyline like Alder was. That is something I didn't care for Steven and Wallace.
Alder - Aside from Volcarona his team is "alright" I am not overly impressed with Alder. I think it would be a bit better if they replaced his Bug types with some other pokes(outside of his anchor Volcarona). I do like his involvement in the story like though, as well as the Gym Leaders.