Even on a 4LT package the Nav system is still a $1750 upgrade. The in dash 6 disc changer is the 'standard' radio.
Neither of the OEM radios will 'control' any ipods. They just have audio input plugs that you connect to your MP3 players headphone output.
If you want all of the bells and whistles your best bet would be to get the base radio and install an aftermarket head unit that does what you require. For $1750 you can pretty much do anything you want to and have it all integrated in the HU. Get last years model and it won't even cost you $1000 installed.