The Sweet-Sixteen is a good rifle, but unless you have a specific reason for wanting *short-distance* accuracy, then IMO it is set up in a contradictory way.
Clearly, these rifles are intended to be scoped and with bench accuracy in mind. With their heavy bull barrels, they certainly are NOT field rifles. However, the short barrel *usually* is out of place on such a rifle, especially for a varmint rifle, where you want a long barrel's higher velocity so that you can reach out farther. The short barrel will require more elevation correction and your bullets will be subjected to more time in the crosswinds due to the lower velocity and increased time to target. As folks like UglyGun will tell you, this is NOT helpful when shooting at little rodents! [:D]
Again, you have to evaluate your needs and the things you intend to do with the rifle in order to get the setup that works best for you.
I would also recommend a standard forged flattop upper receiver (DPMS sells these) over the "Lo-Pro" or the other extruded DPMS uppers, such as the "Hi-Rise". This will ensure compatibility with other accessories later on if you want to change configurations.
I recommend doing a lot of reading, especially in the Ammo and Optics forums, before making any decisions. Things you learn there could well affect your desired configuration, and it's cheaper to get it the way you want in the first place than to replace a bunch of parts later.
-Troy