[Layton13]

For me personally:

Best:
Bano/Gold Drive: Probably one of the best evil scientist characters in the franchise. His motivation is interesting, being afraid of everything he can't control, and a lack of empathy. It was also refreshing to see the trope done well after how bad Duke was.
Gremlin: Perfect villain for Wizard's final. He's a dark mirror of Haruto and Kamen Rider protagonists in general. You just love to hate him.
Hajime: Very good finally with lots of build-up through the show. You can totally believe the friendship and reactions of the cast being pushed into this horrible situation.

Worst:
Kaito/Baron: I hate this guy, and not in the love to hate him kind of way, just hate him as a character. He's a hypocritical idiot that constantly flip-flopped on his beliefs and was nothing more than an asshole and walking trope. Doesn't help that the actual bad guy of the show, Sagrara, gets away scot-free because of him.
Daguva: Beyond an interesting concept, this guy is a big fat nothing! Which just makes it a fight between two dudes in costumes.
Horrobi: I know I'm gonna get shit for this, but I'll get this off my chest. Aruto and Horrobi have no real connection or rivalry throughout the show. Why, if this was always the plan did it feel like this final battle had no build-up at all? And even when it happened, it wasn't about how Humagears should be treated, it was about revenge. You know why? Because that was the only reason this fight would be interesting in the slightest. And worst of all, Horobi's hatred for humanity has nothing to stand on and is hollow. It's not built from experience, it is simply the will of the Ark, which really robes any last chance he could be interesting.