That all sounds awesome and very useful!
The main thing for me was to have all item positions kept the same but for the items themselves to be switched around and for the item lengths to adapt to be the same as the item they have now become.
Your "shuffle order.." is working and the only difference would be for it to be random rather than "shuffled".
I'll try and capture a vid of it at some point as I don't have time to explain well now or anything much at all!
deadlines are drawing near!