"It will be decided, that our Executive Branch will be that of a monarch. Based off from our Intelonian's style of leadership, the Monarch status is a way to lock down and prevent people who think they can change our Ideals that we have settled on. The term Monarch doesn't mean it will be ruled by one/. person, it will be governed by 2, the Supreme Chancellor and Queen, both powers equal so neither side is powerful. Our main government will however will be more Republic-Democracy, our Monarchy will watch over making sure that our government is held."
-Chancellor Amadeus's description of the proposed Monarchy of the Republic

The Galactic Republic's government is entirely based on its founding, the term Monarch Republic as its described, is its leaders are born into the role while its people have the right to decide around. Despite the term Monarch being described as a system of government, the Republic's Monarch is mainly referred only to the Executive Branch. The Executive Branch was the only branch that was planned extensively, the reason why was to prevent the whole Intelonian style of a dictator-monarch.
The Executive Branch Monarch was decided so it will prevent other people who are incapable of running it, it also prevents those are politically corrupt in terms. This Monarch-style can only be broken unless the Royal Family has no-one else to pass it down to, which only happened 3 times out of the entire 91 Royal Families. During that, the Republic Senate will take full control of the Executive Branch (as mentioned with the Act of Succession) and hold that position until a new Royal Family is chosen.

REPUBLIC FACT: Did you know that the Republic's Capital City wasn't actually the Capital, it became the Capital right after the Centennial City Disaster