I love my 2011 3/4 ton Suburban. We are getting a reasonable 14mpg in mixed driving and about 18mpg highway unloaded. It also tows our 6500-ish pound with ease and comfort. The 3/4 ton comes standard with the things people recommend upgrading their half tons anyway, LT tires, integrated brake controller, 3.73 axle ratio, HD trans cooler, etc. The 2008+ 2500s are mechanically the same.
2009+ half tons with 5.3L/6-spd 3.42 is a very good compromise. 20-ish mpg highway, 17mpg mixed. Owners are very pleased with them. I recommend the long wheelbases (Suburban/Yukon XL).
If you only have 2 people in the TV, the Yukon Denali may be cof interest. The 6.2L is strong, gets somewhere between the 3/4 ton 6.0L and halfton 5.3L fuel economy, is loaded with luxury. I test drove one with my TT and was very pleased. But I wanted the more HD suspension for my family.
