Me confused. If you don't race, why the 16 lb weight goal, and why the less upright position? I assume not racing means no crits, but that you still want to be fast and efficient?

17-18+ lb will get you a handful of nice bikes to look at in this price range. For climbing fun, for example, a Tarmac Comp compact is in your price range. So is a Cannondale CAAD9 with upgraded wheels (and if you wait until next year, you might be talking about getting a frame and building it up for that price range). Some might list Cervelo Soloist Team (AL alloy). Lower end Felt. Upgraded Giant from what you have now. Jamis. The list goes on. Try some out, read the forums, mags, reviews, etc. But I'm guessing you've already done this.

Otherwise, if 16 lb is your most important goal, it's going to be hard to achieve in the 2000-2500 price range. There is no magic bullet hidden find that hasn't been exhaustively discussed on here, or reviewed in the mags. Again, I question that weight requirement. You'll do better to go to compact, and a frame that gives you the position you want and the ride feel you want, and not fixate on weight numbers on the bike. The right bike at 18 lbs will feel great, and compact gearing will give you significant benefits for climbing that you're looking for.