Nice.
In my country, 44gallon drums and bicycle wheels are fairly standardized.
In the first build, what did you do about the grease in the bearings? Did you use honey and how well did this work?
In the second build, I think you lose momentum by having the frames so close to the drive shaft, and it can't free spin. You could improve this by fixing the cage and stirrer into the barrel and putting a driver on top, and using a driver in the drill. Speed up and then disengage the drill and it will spin itself out.