Traveling, towing, and lifting a 1/2 GM truck aren't the best things to mix. I've owned several lifted/lowered trucks and tell you from experience, it's not a good idea. I'm not saying it's not safe, it's just that when you put the bigger tires on the truck, it throws the gearing off. The 5.3L GM motor barely has enough torque to turn the bigger wheels, and it really sucks when you've got a load to tow.
In that price range you can get a decent crew cab 2500HD with the Duramax/Allison combo. Of all the trucks I've had, that's the one I miss the most. Fuel economy was the same as the 1/2 ton stock, and when I towed, the mpg was the same. With the 1/2 ton it was less than 10mpg....