The key difference though was she was not brought up to be a Queen Regnant but to be a French Queen Consort. Had she remained in Scotland arguably she would have been more aware of the peculiar and particular problems of the Scots Crown. It is generally agreed that she was the spoilt and petted darling of the French court from her arrival not her fault but a fact.
Whilst Henri II lived France's religious problems were kept more under control, she and her young husband after his accession were largely dominated by her Guise relations who were on the arch catholic side and responsible for really pushing the French into the first religious wars of the 1560's.
She wasn't such an innocent child when she signed the secret codicils to her marriage treaty when asked to by Henri II which in effect turned Scotland into a french vassal state and piggy bank.
Her essential problem was as a Queen from birth she was completely and utterly secure in her position - her pride would never let her lose face or caste that was why she was so determined to marry again as soon as possible and was very very keen that her new husband was at least as high in rank as the dead Francois II - it was purely a coup de foudre and his own Tudor blood that lead her to marry Darnley.
You are right to say that her main problem was her flair for the dramatic which lead her to take reckless decisions and her willingness to trust people she shouldn't have done.
I completely agree. Some historians have suggested that her chances of success as ruling Queen of Scotland were adversely affected by her growing up in France. When she left Scotland she was a Scottish child but when she returned there she was a French woman who viewed Scotland much as the French did - with affection mixed with condescension. Also, on the death of Mary Tudor, her father in law proclaimed Mary and her husband as King and Queen of England and Mary arrived back in Scotland eager to have her claim to the English throne acknowledged. To her, I suspect, Scotland always seemed like a consolation prize compared to the English throne to which her French relatives had taught her was her right.
I'm probably in a minority of one on this, but I honestly don't see that her upbringing in France was necessarily a problem:
1) France was a difficult country to rule with the same religious problems, and possibly worse economic problems than Scotland.
2) Scotland was such a backward country as is portrayed in the Vanessa Redgrave movie. The Scottish nobility were well educated and many ahad spent time at the French court
3) Mary was always known by her title Queen of Scots at the French court (until she became Dauphine). She did not despise this title.
4) During the years of her personal rule Mary did a good job as Queen of Scots ( before she married Darnley). She did nothing to actively pursue her claim to the English throne. Nor did she moan on about how much better things were in France.
5) Mary was a catholic, it is true, but her policy was consistently conciliatory. She did not persecute protestants. In this respects her rule can be compared to that of Catherine de Medici in France. I think Catherine's job in France was far more challenging, actually.
So where did Mary go so spectacularly wrong? It wasn't that she was really better fitted for ruling France. The basic problem was that she wasby nature a poor and, it must be said, a reckless decision maker. I think this was a basic character trait, which admittedly could have been nurtured by her cosseted upbringing. This aspect of her character would have brought her trouble in France or Scotland, or for that matter in any office job!