absolutely agree, wheels first. I suspect your stock wheels are closer to 2000 grams, haven't looked at the actual specs. when you consider wheels, consider more than just weight - depending on how much you way and what you're doing, there are other factors. But yeah you can get a really solid set of wheels online for the $300 range.
If you do your own work, you can actually get something close to a new full Ultegra group for the remaining $700 you have budgeted if you scour ebay at the right time of year. Bikesdirect.com has Kestrel Talons with Ultegra SL for $1500 and you could in theory sell everything except the group and get the group for under $1000.
Now, you may want to work with your LBS, which I can totally get behind. I go to mine for all kinds of stuff, I just can't justify paying double for the more expensive stuff. If you can find a place that will let you try out seats, that's something that definitely requires trial and error.