In answer to your question we own a PARASOUND Halo A521 and A23 coupled with an ONKYO PR-SC5508 (the next model year down from your Integra 80.3). We are also running a 7.2 home theater surround. As far as interconnects go, I have used custom RCA plugs in the past but when we went with the above set of equipment, I wanted to make sure there was no degradation at all, period, between the pre-amp - power amp stage (the weak link) so we went with Emotiva's excellent "X Series XLR interconnects".
Some say that "XLR interconnects are only needed for longer runs". That may or may not be the case, as for me, I didn't want to take any chances.That said, the way XLR cables are connected between the preamp and power amp is a much more secure, and to my mind, a much more precise way of connecting, and securing the interconnection between the gear.
Just compare the precise and secure interconnection contact points and detailed construction of Emotivas XLR cables (they are built like a tank, see diagrams and illustrations on right hand side of page) with an RCA cable and you will see what I mean:
As opposed to RCA cables, the XLR cable is securely locked into place once it is installed/connected to the unit and it isn't going anywhere. From numerous first-hand experiences of RCA cables working their way free once installed, that can not be said of RCA cables.
Having spent the kind of serious money we did on the exceptional quality gear listed above, I had no problem spending a few extra $ to insure the best connection possible. My gear, like yours is surrounded by other powerful equipment, wires and electricity and I didn't want any stray signals getting in the path whatsoever and that is the case with our XLR cables.
If there were no possible benefit to balanced XLR interconnection, PARASOUND wouldn't have wasted their time effort and money by bothering to design or to install XLR interconnection capabilities to their Halo line because it makes no sense.
And having listened to both RCA and XLR, the XLR cables do sound better to my ear, but as opposed to all of the reasons listed above, that one argument is "subjective". Still, they are MY ears and I am the one listening to it and I am the one who needs to be totally satisfied that I am receiving the very best sound the equipment is capable of producing and you do too.
Should I also go with XLR interconnects? You are a big boy, do the research, seriously take all of the reasons listed above into consideration and make a decision
As for speaker wire that would compliment these units: check out Monoprice.com They have very good speaker wire at a reasonable price.
The only thing I would add to your above list which made a tremendously big difference in our own audio set up was applying gold-plated banana plugs to the positive and negative connections on either end of the speaker wire. These plugs just do a better job in connecting/securing the wire path to the power amp and speakers. I couldn't believe the difference this simple addition made to the over all quality and clarity of our sonic experience. The only thing I can liken it to is clinking together "crystal glasses" from Wal-Mart to the sound made by clinking together a fine pair of very expensive and thin Wedgewood crystal glasses: Both make a "noise" but there is no comparison between the sonics: one is a hollow, lifeless "clink"; while the next produces a rich, vibrant clinking "ring" which resonates, echoes and vibrates producing a harmony of ethereal "music to the ears". That was the difference banana plugs made to the sonics. Even my wife, who normally doesn't notice or say anything regarding audio equipment commented on the difference and amount of clarity and new "detail" she heard once the banana plugs were installed.