I've played Fancade some with my six year old.  It feels just shy of awesome.  The engine certainly has a ton of flexibility.  The voxel style does an excellent job of setting expectations.  It doesn't come as much of a surprise, but it's always disheartening how difficult precise control of 3D objects on a 2D screen.  Despite feeling that Fancade is much easier than practically any kind of modeling, still putting together a satisfying character is surprisingly difficult.  The clickable node edges programming blocks are really cute, but it's hard to figure out how to use them properly.  I mean suffers from mostly the same problems as any structured editor.  I don't know.  I want to like Fancade.  And some really well designed course around it could help, but it's not quite there.