This design gets to the core of what Wonder Woman is all about. She’s a creation of the gods and so she needs to maintain that sense of regalia. Jim Lee’s redesign, while not an utter failure has brought the costume to a street level. In other words, it’s too “black canary”. What you've done is to take the Wonder Woman costume and fix many of the impracticalities (which is what Jim Lee set out to do), but you've retained the elements that make her a Wonder and not just a kick-ass Woman.
I’ll preface this by saying that I think the only improvement I could suggest for your design is to opt for a more practical foot-piece over high heels, even though they do look foxy.
On the whole, your costume seems wearable. The previous design always made me ponder a few things, like how much it must hurt to wear the bracelets. You solve this with the cloth gloves that hold them on.
Also, the previous design made me wonder how such a heavy breastplate with no straps can stay put during an acrobatic fight. It was a recipe for slippage. You solved the problem by connecting the eagle’s head from the breastplate to her neck piece.
The previous design used the headband more or less as a tiara, for aesthetic purposes and for no other practical purpose. You made the headband into a useful piece of armor without detracting too much from Diana’s lovely face.
Your design carries through the color scheme we all know and love; patriotic without making it a direct reference to the United States flag like the previous design, and without losing it entirely like Jim Lee’s design. The emphasis on the gold elements makes your design just gorgeous and plays up Diana’s bronzed Grecian skin tone.
I absolutely love this design and hope that it appears at some point on some version of Wonder Woman. Movie perhaps?
Very nice. Much better than the design DC ended up using, but I guess if they had gone with a real nice redesign like this one it would be harder to return to the original costume, as they are bound to do eventually.