I wish the skirt were poofier.
As you can see below, both petticoat and top are attached with a bead-and-loop. This works surprisingly well. If there were any clothes on top of these, though, the lumps would be visible. A button would lie flatter and look more 'real', but I didn't have any sufficiently small.
Lessons learned : Beads are lumpy, shirts cannot be rectangles if the doll has any curves at all.