KKC: I'd say if you are in doubt and can still get your money back, then return the lens. (That's my general rule that I apply to almost everything I purchase that has a good return policy--if in doubt, take it back.) You can always purchase it later if you become more certain about your decision. If, however, the full money back return period is over, then it sounds like you might need some PPR: post-purchase reinforcement. From what I've read and seen from other posts and threads on this list and other websites, the 16-35 II is an amazing lens. (Full disclosure: It and the 100 mm L macro are the next two lenses I want to get.) I'm sure that there are many websites that can provide inspiration. And, from the photos you posted, they show that the lens can deliver absolutely wonderful and rich colors. So, if you can't return it for full price, then I'd suggest hanging on to it for awhile and using it as much as you can. Love isn't always at first sight. But, if you don't grow to love it, you can always sell it.
+100 ...said almost the same thing...more inspiration