Many, many thanks Mari!
The reason I'm interested in the portrait by Drouias (said to be the most expensive French painter at that time) is that said painter was originally selected to do the portrait of Marie Antoinette in Vienna but Joseph Ducreux (less expensive) was substituted at the last minute, of course due to some court intrigue at Versailles. So apparently, whoever commissioned that portrait of Maria Amalia was willing to pay very good money for it while the future Dauphine (and Queen) of France was assigned a less expensive painter. I doubt if Maria Amalia commissioned it herself; I've read that she hated anything French. I also think it is one portrait of Amalia that is not very well known. I do know some Italian so perhaps I will email the Galleria Nazionale di Parma on the 'Diana' portrait of hers. All I know is that Carlo Angelo dal Verme was a nobleman-painter who was from Milan, I think.
I've read ugly, mannish and horse crazy (as well as with dogs, too)... I've even read her being described as a Messalina or Agrippina and that she had live wolves brought to her to kill. I think such accusations are outrageous. While she was outlandish and very contrary to Maria Theresa, Spain and France, Maria Amalia was not evil. I think most historians/authors who paint(ed) her as 'evil incarnate' (or similar) simply forgot (or overlooked the fact) that Parma was a sovereign state and Ferdinand and Amalia could do whatever they wanted with the duchy. And both wanted to be free of France and Spain. As for her not obeying her mother, well, it was already pointed out in this thread that she didn't have to obey Maria Theresa or France's wishes or Spain's; she was, after all, under the authority of her husband. IMHO, I think Maria Theresa has done much worse things than her, such as the partition of Poland, the Seven Years War, her severe oppression of the Jews and Protestants, etc. Of course, that doesn't excuse Maria Amalia's faults - she had many and was certainly no angel (Maria Theresa herself thought 'angels' such as Leopold's wife were only to be admired but not imitated) - but l think most historians have judged her quite harshly (the very reason I got interested in her in the first place). If she was so awful, why did Parma's people love her or how could she have earned their sympathy? She must have done something right.
As for Louis XV saying those words against her, well, his words doesn't seem true. Marie Antoinette's departure for France was deliberately moved to an earlier time in the hope that it would avoid the extent of the distress that happened during both Caroline's and Amalia's departures from Vienna. That doesn't sound like the departure of an unliked family member. One must also remember that Amalia seemed to be the only archduchess who was close to the older set of siblings as well as the younger set. I'm talking about Marianne, Elisabeth, Caroline and MA in particular. And she also received visits from her brothers Leopold, Maximilian, and Ferdinand. IMHO, Louis XV was fed up with Amalia at that point. And did Ferdinand heed him despite his words? France and Spain wanted to break them up but nothing happened to such plans.
Amalia's eyes were described as cerulean/azure blue. I think she was also described as having a beautiful figure so 'sexy' does fit. I wonder about that rough voice. I've read some accounts where Amalia was praised for her beautiful singing voice. Certainly, Il Parnasso Confuso (which she performed together with her sisters Elisabeth, Josepha, and Caroline during Joseph's wedding to Maria Josepha of Bavaria in 1765) was technically challenging; opera singer Julianne Baird in recent times recorded said opera and she said that they (the cast and other musicians) were surprised at the 'vocal acrobatics' of the opera----and pointed out that they were professional singers, unlike the archduchesses. Metastasio also waxed poetic rapture about Amalia's enchanting voice. Dorothy Gies McGuigan in the book The Habsburgs described her as a coloratura (soprano). And Duke Ferdinand certainly thought his wife had a very pretty voice and expressed his deep regret about how a visitor (Lady Mary Coke) wasn't able to see her perform at the opera.
I've read that after Tuscany, Parma was the next best governed state in Italy, despite the fact that the reforms were stopped after the dismissal of Du Tillot. Seems like Ferdinand and Amalia did quite well, despite being on the conservative side and not being 'enlightened'. An English noblewoman described Parma in 1790-91 as quite prosperous and said that Ferdinand was kind ruler-- i.e. no new taxes imposed and no petition was denied. It is no wonder the people of Parma helped the ducal couple pay Napoleon's demands in 1796.