[IXRollOutIX]

I've got a very similar list, although I feel like there's a lot of limitations here seeing as some of the main riders have very few forms. I think this thread might support more options if it was generalized to favorite Rider suit designs for each year, secondary (and so on) included. So forgive me, but I'm going to do that instead.

Kuuga: Ultimate Form
Agito: Ground Form
Ryuki: Knight
Faiz: Default
Blade: King Form
Hibiki: Ibuki
Kabuto: Rider Form
Den-O: Sword Form
Kiva: Default
Decade: Default, I suppose. (Although technically probably Kabuto or Hibiki form.)
W: Fang/Joker
OOO: Tajador Combo
Fourze: Meteor
Wizard: Infinity Style
Gaim: Kachidoki Arms
Drive: Type Tridoron