Relocating the stock one is just to keep you from getting error codes when certain services are performed. At this time if you pull the HU, you lose the L7 amp, and you need some way to power all the speakers. We have a kit with an MS-8 and a woofer amp that can do that for you, with an integration harness.
The Sony 7" nav kicks ass. It's more work to install, though.
That kit isn't in right. That's not how any head unit should look in the dash.