While there's merit to the " race what you got approach" and you don't need new wheels, it is nice to have two sets of wheels (among other things to put one in the wheel pit)

So if you buy a good set of wheels, you'll accomplish several things, 1) a modest performance improvement, 2) flexibility of having a backup, and 3) you'll have a nice set of wheels for you next bike.

In your price range I'd look at 50mm deep CF Tubulars from Psimet for $699. www.psimet.com