I had an older Dodge 1500 which I hated. No power and the brakes were horrible. I went to the 06 diesel after comparing Ford and Chevy. Chevy was too expensive but has a nice transmission. Dodge had the Cummins. The brakes on the 06 are awesome. The comfort level and reliability are excellent. I pull a 50 hp Kubota tractor on a large trailor with implements with no problem. I'm getting about 18 - 20 mpg on a mix of highway and street driving. I find the back seat of the quad cab adequate for my needs. I'll be driving this truck until it or I won't go anymore.
The exterior design and power when I need it. The open engine design. It is easy to perform standard maintenance on this truck.
The only real improvements would be a slightly more powerful A/C and put the Allison transmission in it. Add a GPS and a bully dog to the base model while keeping the price down.