[Brainchild]

This is actually a really tough one. I don't own a whole lot of Rider figures, but I think I'll have to give my love to SHF Fourze Base States for favorite figure. The whole package just works really well. The figure's design really captures the character with all of the hands and the module gimmick is integrated pretty well for what it is. My only qualm is that there was no stand, so the drill is kind of useless if you don't use one.
As for my favorite Rider... hm. I think character would go to OOO, Garren or Meteor. Shoot, that's a hard decision. Design-wise, I like TheBee, Kaixa and Sasword a whole lot.

It's kind of a difficult choice here, but balancing out favorite character, design and figure, I think I'd give it to SHF Meteor. I'm a total Fourze fanboy, so call it personal bias, but man, I like that guy.