Okay, so... The two champions I liked the most are Urbosa and Revali because I think that their voice actors were by far the best. Urbosa because you look at her and the voice comes out and you're just like... "yeah that's the exact voice that needs to come out." And Revali because... just... I dunno, Sean did just an incredible job with all the little nuances and affectations. I spoke to him personally over FB after playing BotW, going so far as to look him up and tell him as much after hearing him in an interview in Zelda Dungeon's YouTube channel. But also, both characters seemed to have the most depth. And I've only come to like them more after seeing them here.
Daruk, to me he was sort of a non-entity in the first game. He was just so stock-trope there just felt like nothing there. But I feel that his voice actor has improved and he's got a little more to say and do here, and I like how he shares a few looks and moments with Urbosa. Of the champions, they're both the actual leaders of their people so you can see they kinda are on the same wavelength. What others need a conversation to convey, they share with a look. And I like that.
Mipha... I loathed her in Breath of the Wild. I was glad she was dead. So I wasn't sure what I'd think of her here. But I actually think better of her after this game. I will likely never like the character, but she's at least graduated to neutrality in my opinion. Though, from a mechanical standpoint, I understand she's probably good but I still have no real desire to learn how to use her. Sidon, on the other hand...
Purah is now pure Cringe Incarnate.
Kohga is pretty funny, I like his voice actor and his voice clips.