I think that would be a nice starter system. Cables can make a difference but how much depends on the systems resolution or capability to allow you to hear how much difference. The KLH are alright to start with but they aren't going to be very detailed. I like Onkyo receivers they have a strong amp section.

I recommend Blue Jeans cables as a good starting point in cables. You can see my "impressions" under the "Cables" forums. BJC are not expensive and do very well.