Out of everything, I still like Caesar's sequence best of all. Probably because I generally like initial henshin sequences for a rider series than I do for Sentai, and his definitely feels like the more traditional Rider style, where as the others have a more Sentai feel to them.
I will give them points however, for having the 4 that appears in this game all distinctly different. Can't wait until the next game to see the 5th knight.
Sadly though I'm at the point now where I don't even need to change to take down the knights. I can just beat them down with my avatar.