Character mistake: President Marsdin says that Camp David was named by President Eisenhower in honor of his son and grandson. It was actually named for his father and his grandson; his sons were named John and Doud.
Other mistake: Supergirl walks into the gallery returning the painting, says "di nada", then takes off straight upwards...presumably blasting her way through the ceiling.
Answer: Another part of why the change was that it's cold in Canada in the winter and the old costume didn't protect her from it, whereas the new one is nice and warm.