I have a Sony DDWG700 and it sounds awesome.
I use from time to time the Digital Cinema Sound EX. (DCS), those settings gave me the posibility to add some reverb and depth to the sounds.
They recreate (A being the Cary Grant sound stage for dialogue, B being the Kim Novak sound stage for action movies, C being the Entertainment scoring stage for music, which is pretty interesting indeed.
It feels weird at the very beginning, but the sound DOES actually bounces differently.
The settings in GT5 are set in Large Theater and DTS 5.1.
Also, in other cases, I have changed another settings in the HT, representing in this cases differents types of rooms for music. Hall, Jazz Club and Live Concert.
It reproduces the acoustic of a classical concert hall, the acoustic of a Jazz Club and the acoustic of a classical concert hall of 300 seats respectively.
It sounds, again, weird when you read the description, but they have a really good result depending of the type of movie or concert or whatever you're watching.
Those settings with GT5 helps the game's sound a lot.
By the way, your receiver, decodified only Dolby TrueHD but not DTS-HD Master Audio or I'm dreaming?