And was usually described as beautiful and charming, by her contemporaries.
Maybe. Ronan is a very talented young lady, but the role really should have gone to someone more... physically impressive.
So they should have gone with Jessica Chastain or similar?
shareI think the actress is tall enough for the role, and has the right look, despite not being the prettiest they could have chosen, but the Scottish brogue and the "wild, untamed Scot" look does not work well for her.
What I also find ridiculous are the clothes and overall look they gave her. They have her running around with her hair wild and messy, with a fake, heart-shaped hairpiece on the top of her head. They also have Mary wearing dresses made of DENIM, of all things, (when such a fabric didn't exist back then, and she's wearing a lot of styles that can only be described as "steampunk." It gets even better. She wears six hooped earrings in her right ear, which the real Mary DID NOT. Now there is a famous portrait of an Italian noble from that time period wearing six hooped earrings in their right ear, but that does not mean Mary did, or someone would have mentioned it.
To show favor towards Queen Mary, they choose a slightly less attractive actress for Elizabeth, and have her wear even worse clothing and hair pieces. And of course, once again, they give history the middle finger and have Elizabeth and Mary meet each other face to face in secret, when that NEVER happened in real life. They only ever communicated through letters and intermediaries.