chateauroux said:
He would have been in his mid fifties by the time his father died so chances are his reign wouldn't have been a particularly long one.
Le Grand Dauphin was born in 1661 and his father The Sun King died in 1715: he would thus be 52 years old upon his father's death. As for his potential lifespan, remember that Louis XIV died four days before his 77th birthday while OTL Louis XV (the Grand Dauphin's grandson) died at the age of 64. If the Grand Dauphin became an ATL King Louis XV of France, it's still possible that he could reign at least 10 years. Which seems pretty average in terms of rulership length, even if a bit short.
chateauroux said:
Also, he doesn't seem to have been a very dynamic personality so probably wouldn't have tried to change the status quo.
That is actually debatable as while he wasn't very active, he still had an entourage, made notably around two of his half sisters, and that entourage notably opposed the policies advocated by his son, The Petit Dauphin. The Grand Dauphin was also opposed to the removal of the Edict of Nantes when Louis XIV proclaimed it: that doesn't mean he will repel the ban it but it does show that he wouldn't be the same King his father was, so he might not like the satus quo.
chateauroux said:
If his son had survived measles to be King things might well have been rather different. I think Bourgoyne was quite forward thinking and might well have tried to implement a gradual change as to how France was run. For a start he might have tried to reduce the etiquette and ceremony at Versailles and might even have decided to move the Court's base back to Paris at some point, perhaps realising that to be a good King it's important not to be too isolate from one's subjects.
The Petit Dauphin was mostly influenced by the
dévots, who were opponents to the Absolute Monarchy that Louis XIV had created. They wanted a less centralized monarchy controlled by the Aristocracy: the provinces would have more power and there were to be intermediary councils between them and the King. These councils would be only made of Aristocrats because they were perceived by the
dévots as the only ones qualified to serve as intermediary between the King and his people. Part of their ideas were tried by the Regent OTL in the form of the
polysinodie which was basically several councils assisting the King. It proved however deeply ineffective (because of the people who made them) and was abandonned in 1718.
That system doesn't really look to me as "forward thinking", except maybe in the idea that the government shouldn't be as Centralised and Absolute as it was. But it limits the governmental position to only the high nobility: it's more restricted and less inclusive than the system Louis XIV put in place. It doesn't make the King closer to its people from my POV, it creates an even greater distance. Granted, it's possible that the Petit Dauphin might realise the need to include more than just the aristocracy in the long run but nothing guarantees it. I also don't really see how that would push the Dauphin to loosen and reduce the Etiquette and Ceremonies: if anything, that might actually push for more Etiquette.
The return to Paris is a likely possibility but not necessarilly because it would have the King be closer to its people. Versailles was primarily a symbol of Absolutism and Louis XIV's power, as well as the result of the latter's childhood: Louis XIV had been traumatized by his flight to Saint Germain during the Fronde and always was weary of Paris as a result. And the decision wasn't completely bad too as Paris as a high tendency to oppose the central government historically: let's not forget Paris was the center of the Ligue during the Religious Wars, and the capital had already supported the English during the Hundread Years War (at least the University of Paris did: that's why the Kings of France traditionnally chose their physician from the University of Montpellier). Coming back to Paris would thus simply a symbol to show that things would change and that the ways of the Sun King were abandonned. It would mean nothing in regards to a will to get closer to the people.
In other words, the Petit Dauphin would likely have been an extremly conservative ruler.