For the love of god, please go window -> styles -> simple (or anything but engineering with corner hatches). Also try downloading the Sutton Place model from the 3D warehouse so you can work in some sort of realistic(ish) scale. Wyliepoon made one.
And better yet, download Vray for sketchup..
aaaand to stay on topic:
with some replaced windows that preserve the modernist / international style, while being cleaner, more simple and energy efficient, this building could be gorgeous! The current windows look pretty rough.
I'm excited to see how they deal with the ground level here. Keeping the window style while respectfully adding doors in them for retail would be interesting. Hopefully we get a good sensible firm to tackle this one.