A receiver is three products built into one box:

Tuner-Either AM/FM or just FM.
Preamplifier-Offers source switching and volume control
Amplifier-Drives the speakers

An integrated amplifier is a receiver minus the tuner.

The Rotel RX-1052 is a great receiver, by far the best stereo receiver I have ever heard that is on the market today and I don't say that lightly. Part of that is due to the fact the high-end companies don't like to build receivers (partly for performance reasons, but at least partially because of image issues.) Some people find Rotel a little "bright" (meaning that they feel it has a little too much high frequency information in the sound.) But others would feel that the NAD are too "warm" (a little too rolled off in the high frequencies.) I've recommended the 1052 to many friends and the ones who took my advise never regretted it.

I'd recommend looking at a REL subwoofer. Their ability to expand the soundstage is remarkable. They integrate more seamlessly than any other sub I've heard. When properly set up the sub is not a source of audible sound, it just sounds like the left/right speakers have had a major increase in bass extension. Of course that sounds like a description of what ALL subs do, unfortunately they don't. RELs are the perfect sub for those who want musical bass, that perfectly matches what a great speaker can produce.