Glass is really a neutral material. Therefore it's important for glass buildings to have a good design. When a building is designed essentially as a box and then skinned with glass, of course it's not going to look great. FMC and Cira Center are great examples of glass skinned buildings done right.
I do agree that the blue/silver glass is getting a bit old. I'm disappointed in CTC's skin - the model that was on display gave the appearance of a darker, almost black colored glass, which would have been really cool.
What I'd really, really like to see is a 700+ foot Art Deco tower (think
40 Wall Street) but I think we missed the boat on that. The biggest casualty from the Gentleman's Agreement is a lack of early 20th century limestone skyscrapers (500+ ft). There are plenty under 500 feet, but they just don't make much of an impact on our skyline.