Presidential System would apply Separation of Powers. Today, there is no such thing as Separation of Powers. We don't even have one mechanism to decide government and parliament induvidually. Today's system is like a Dictatorship. Elected political party rules everything, both legislature and executive powers. Elected party does whatever it wants. We need Presidential System. In Pr. System, people will elect government and parliament induvidually with 2 different elections. People may give these powers to one political view, or may give that to many.
And there will not be questions in people's mind about Government members, before election. All President candidates would give their Minister candidate lists to the Public, so Nation will directly elect the Government. Instead of one Political party leader that decides everything like Padishah. So, Presidential System is far way more democratic than today's system.