Yeah! The stage builder! It's awesome! I'll post some pics tomorrow, probably, just bug me about it...but...I made a stage!
It's set in the sky/mountainous/ruins motif, and it's probably the most awesome stage ever. You've seen the Mother 3 stage, right? Well, it's about that size, but the differences include a central battle area, several moving platforms, and springs at the bottom, to save yourself from falling off. Like I said, I'll post some pictures, and maybe even video tomorrow, but the stage builder is a much better feature than I thought it would initially be.
Of course, now I need to figure out if there's anything unlockable for it, but I haven't found any new pieces yet.