If you're that into your audio, you should know that no built in amp is ever going to be as good as a good standalone/specialised amp. So do it! You won't regret it.
As for the deck, if you've got the screen and want that to hook up with DVD, TV etc like mine, there are a few options. My Clarion is great, and it has a 7" pop up screen to boot. I went that way because I wanted absolutely everything in the deck, and I got it: DVD, AV IN, iPod, Bluetooth, and even an extra front AV IN. If you're willing to go without bluetooth, there are a heap more options. Iain also has a Clarion which doesn't have DVD, runs entirely off digital media.