yeah this is clearly over engineering. Maintenance, initial costs (resources and assembly), and effort to retrieve the water, are all excessive for this design, given the technology used. If she simplified this design down to something that used less buckets (effectively a crankshaft, pulley, and bucket) everything would be better.
This is the design you'd use, if you attached a motor of some sort (ie. wind mill or water wheel), but didn't have access to ample metals to make a pump.