The light which floods downtown Chicago has a special clarity & intensity that really rewards texture & surface variation. The light plays off Brutalist (concrete) buildings like 55 W Wacker & the Metro Correctional Center especially well, IMHO - it seems to morph them from moment to moment as the angle of the sun or degree of cloud cover changes; conversely, Chicago's light seems to cheapen flat, undifferentiated, reflective surfaces like those on Bofill's Chase Plaza (an exception, though, for the concave 333 Wacker, which is like a funhouse mirror...)
What excites me most about the Aqua design is its promise of surface & texture variation, and the tension it creates between smooth glass box & brutalist terrace - it will fascinate as the light & weather change, or as one moves towards or away from it.
Of course, the devil is in the details, so a good execution is really, really important...But what I've seen to date in the renders makes me really happy.