Remember, a half ton of today has more horsepower, and better brakes than a 3/4 ton from not so long ago... But, and it's a big but, all half tons are not equal.
The Chevy 4.8 is just underpowered, and Chevy puts relatively high rears in their small V8's.
Today's half ton V6 trucks have signifantly more power than the last Gen V8s (Chevy 4.8, Ford 4.6, Dodge 4.7 ect).
For your TT, a properly equipped half ton (keywords properly equipped) will suit you well. Make sure you get the maximum towing packages, and find your specific payload and capacity. Yes a 3/4 ton diesel will tow better, but as a daily driver it definitely has significant drawbacks.