Gustavus Adolphus said:
In OTL Louis Grand Dauphan was heir apparent but he died in 1711 of smallpox before his father died,... So what if he loved and Became ruler of France instead of Louis XV butterfling away Louis bad policies and potentially averting the French revoulution, what do people think...

First things first : Louis the Grand Dauphin died of smallpox, as did most of Louis XIV's family. By this I mean the two sons of the Grand Dauphin (Louis le Petit Dauphin and the Duke of Berry) but also the eldest son of le Petit Dauphin (an older brother of Louis XV (also named Louis for that matter...) who was just one year older).
If the Grand Dauphin is to survive, then you will have to decide how he will survive : No smallpox in the royal family? Or him being spared, like Louis XV?
Anyway : if Louis le Grand Dauphin survives, then he will become TTL Louis XV while OTL Louis XV will become, depending on the scenario, Louis XVI (if le Petit Dauphin and his eldest son still die), Louis XVII (if Louis le Petit Dauphin or his eldest son dies) or a minor member of the royal family (if Louis le Petit Dauphin and his eldest son do not die). This would also butterfly the regency of Philippe d'Orléans, Louis XIV's nephew, since Louis le Grand Dauphin was an adult and in his 50s.
Given the long life that both Louis XIV (died at 71) and Louis XV (died at 65) had, we can expect Louis le Grand Dauphin to rule for 15 or 20 years before his successors comes in, whoever it is.
As for how the reign of Louis le Grand Dauphin would be, I have know idea... He said once that he didn't try any intellectual effort, which would make him stupid. Yet, because of a dispute with his father in his last years, he was also the center of the opposition to Louis XIV's policies...
Thus, maybe he could become an "enlightenned monarch". If so, this could butterfly away the French Revolution.