She, along with all of her retainers, strive for as much historical authenticity as is reasonably doable in the 21st century, and I think everyone looks amazing. One thing I think she needs, however, is a replica of the black pearls the real Mary is wearing in this portrait:
Mary had many other jewels, but I think this will do for starters...as soon as I can manage to estimate how many pearls I need to get for this extreme opera-length strand and the headpiece, as well as the pear-shaped earrings.
No, silly, not real pearls. She's not a real queen. :)