Lewn.
"If, in fact, you do upgrade, keep a couple of things in mind. Not all equipment and not all cables that have balanced connections are really balanced. With equipment, it is expensive to make a component fully balanced because they have to double up on all the internal parts in the signal path. A lot of companies put xlr connectors and lable the connection balanced, but it is not really balanced. If you are not sure, there should be 2 sets of specs (balanced and non balanced) listed for the piece. If only 1 set of specs, it probably is not balanced. Cables need to be balanced as well, not just have xlr's. The cable should have 3 seperate conductors or, at the very least, 2 conductors and 1 shield. I hope this info can help you with your decision."
The above quote is from my response above. It looks like we are both in agreement. Your post basically says the same exact thing mine does, just in your own words. As far as buying the better connectors, I still have to disagree. It just doesn't make sense. I'm guessing that the used NAD is worth a few hundred dollars. By the time you get done reterminating the cables and/or buying the expensive XLR you will have a good portion of the total value of the NAD invested. The money can be used, instead, for better equipment. So when the OP wants an opinion on choosing either cables/connectors or equipment, I say why spend money to make a small difference when you can put it toward something that will make a big one. Also, if and when the equipment eventually gets upgraded, there is a very good chance that he will probably be going with balanced equipment anyway and will need everything just as it is now. Anyway, thats just my honest opinion on how I see it. Everyone does things their own way but as long as you end up where you need to be and are happy, that's all that matters.