She is very attractive - shape, hair etc.. And she looks stunning.
I am with Brie wrt length, I think in this case just below the knee might be better.
It must be a real challenge to adopt a FLOTUS wardrobe - because image, fashion is a traditional part of the role, and balancing this with your own tastes, practicality, choice of designer etc would take some work. Maybe being attractive/ex model makes it harder because expectations are higher - what were the comments on Laura and Barbara Bush's fashion - I honestly cannot remember (ETA not meaning they are not attractive, but that their background was not as a fashion model).
NZ has had two female leaders, one for less than a year, and one for nine years. Helen Clark, who is one of the most intelligent leaders we have ever had, was constantly criticised for her wardrobe choices (and appearance which is even worse), which seemed blatantly unfair when our male leaders were often dressed in very average attire. Our recent PMs partners/wives have taken a very low key public role. Our new PM's wife (he took over in December) is continuing her work as a GP (Family Doctor).