Benevolent dictators don't remain benevolent for very long.
The writers of the US constitution were very fearful of pure democracy hence the property ownership requirement and limited voting demographic to give voters a stake in not voting money out of the public treasury (and that Federalism is designed such that local states fight a central government over resources and power keeping it in check). The same thing can be achieved by a completely flat tax without exemption.
Originally the Senate was appointed by states (not directly elected) as was the President (appointed by electors sent by the state legislatures). Since legislation had to clear both the house and senate, the senate served as a deliberative body and (having the local best interests at heart) would stop bad legislation. The constitution served as a flat stop as well--providing concrete limits on the government and its powers. Electing the president via state legislature also limited the ability for mob rule voting to put someone at the helm who handed out goodies to those placing him--or her--there (this was torpedoed in a gradual process having its roots in the 14th Amendment paving the way for presidental election by popular vote. NOT the intent of the founders who had set things up for only the house and state legislatures to be able to be directly elected). The US was originally set up as a collection of individual autonomous states held together in a common defensive and economic alliance.
The 16th and 17th Amendments were "logic bombs" toward the US charter by allowing widespread taxing authority (resources) as well as senators now to be elected by popular vote instead of appointed by state legislatures (paving the way for resources being used to buy votes rather than having to be appointed by a legislature acting as a buffer with the individual states' best interest in mind). Took 100 years but we are reaping the "rewards" of this now--as we are by miscreants with excellent rationalization skills watering down the objective rights and limitations affirmed in the US constitution as to make it meaningless.
So it CAN work but demands more vigilance than most cultures can muster--at least over time. De Toqueville was right in this regard. Eventually factions are manipulated by those with an agenda to the demise of the whole.
Kinda like a certain offer which comes to mind which folks only have one more day to think about.