The problem I have with the theory that the Ramseys hid JonBenet in the suitcase and planned to dispose of the body after the cops left is that it has been determined that JonBenet's body wasn't moved after death. It is likely she was in the wine cellar the entire time, in which case the Ramseys had to have thought she'd be discovered pretty soon after calling 911. I don't think they were obtuse enough to believe they'd be left to their own devices after reporting a kidnapping. LE would have been camped out in the neighborhood canvassing neighbors and monitoring to see if the kidnappers attempted to contact the Ramseys again.
The suitcase body removal sounds like a PR hair brained idea as in she thought JR could just walk out of the house with the blue suitcase to go to the bank alone during which time he could drop the body somewhere, collect the money and return home. I would think JR's eyes would spin in his head at the stupidity of such an idea, knowing LE would search any attache' he left with even if he COULD, with one hand, lift a suitcase with a body in it like it was empty. Ha.
I just do not personally believe that the blue suitcase was ever in the plans. It was just one more piece of junk in the basement.
JR would have left her in the basement but maybe not the WC and definitely not latch the door. Latching the door is PR's touch. In the WC, she is not just hiding the body, she is hiding the deed.
PR is written all over this scene. I wouldn't be surprised to learn that when French was down there, a Christmas decoration hung from the top of the door, hiding the latch. He thought it was painted shut. Why? Because when he looked at the top of the door jamb, it was covered in garland and he didn't seen the latch. Otherwise, he would have opened it. On his first trip to the basement, he removed it.
JMHO