Elebits. I just picked up this launch title at Gamestop, and it's very good! Surprisingly long with lots of extras such as Edit Mode and multiplayer! Wouldn't it have been great if there was an AT in which a bunch of Elebits just fell from the sky and started zapping people with electricity? I know that's...not really what they do...they mostly run and hide, but still.
What Assist Trophies would you like to have seen? A couple others might have been Zak and Wiki, Dewy, Chibi-Robo, ect.