"Pirates are monsters" seems a tad mundane to say considering the time and enviroment hey were usually from. It wasn't a world like the one today.
Not saying that makes it right, but they were a element of their time, just as Vikings raiding British monestaries.
The historical and cultural context of monstrous acts makes them no less monstrous.
Romans throwing Christians to wild beasts appear to be an extension of earlier Roman religious rituals where armed men battled beasts. When the armed Romans killed the beasts, it showed how they were favored or blessed. When unarmed non-Romans were torn apart, it showed how Romans were better than the non-Romans.
Over time, these religious rituals became larger and more elaborate, and the religious aspect became mostly trappings.
But why should that background information change the way I view someone tossing a member of a religious minority into a pit of wild boars so they can be gored to death before a cheering crowd?
Moreover, why should that change the way I view someone in Thedas doing the same? They're not the product of synoptic reality. If you want to show me someone performing bloodsport as an extension of archaic religious rites in Thedas, then you need to provide that context, and even then I'm less likely to think it's not monstrous and more likely to think it's a comment on how ritualistic behaviors can lose all meaning and warp in unusual ways.
But that's neither here nor there in regard's to Isabela. I don't need real world historical context or Thedas specific social commentary; I have ample literary context for pirates and I have Isabela's explanation for why she became a pirate. Isabela's desire for freedom from authority and enjoyment of the more thrilling aspects of life fit well into the tradition of pirates as scallywags and daring rogues.
Well I did have one thought: Is it possible the armoured boots are so big because she's wearing her fancy shoes underneath? Seems like a respectful compromise for an Orlesian.
Not so much boots as hardcore slipper protection?