Tell us about yourself!
I think instead of para cord I would have opted for a chian similar to a bycycle chain but much longer and have a crank, heck other than the chain length all you need is an old kids bike and use one of the pedals as your crank. Pulling something REALLY heavy up with paracord sounds painful to me unless I wore gloves.
The spray can w/ ball inside is a great idea. But if I weren't uning a spray can of paint I would line the inside with some thick cloth, an old washcolth perhaps. That way if your stash is a dozen or so Gold Debloons one wouldn't hear metal on metal when picked up. Just a thought after reading this.