Make sure to play with placement when the SCS-01s come. Looks like you have some room on either side to move the speakers out a bit, which would also allow you to try moving them forward off the wall a bit to see how that sounds.
Have you tried some other subwoofer placements?
Actually what you see pictured here is the end result of my latest round of speaker/sub rearranging. Before I had the sub placed inside the left main and perpendicular to the wall - seems as if I had some issues with reflected waves that were playing havoc with my low end, so I decided to move it out and put it at an angle as you see. I wanted to keep the sub closer to the front soundstage however, so this ended up pushing my mains in a lot more than they used to be.
Now, that said - when I'm seated on the couch and listening to a soundtrack/music, whatever - overall it sounds much better than before; the bass is tight, controlled, and I've yet to really perceive a significant difference in the width of the soundstage. Noticeable yes, but it still seems very open and most importantly... accurate.
I'll probably experiment a little more here and there, just for kicks - plan on getting a Great Gramma pad for the sub at some point to further decouple it from the hardwood flooring, and may push it further to the left so I can open up the mains a little more again.
As for the speaker cable - you can't see them, but I use basic 12 gauge Belden from Blue Jeans, heat shrink wrapped at the ends where I stripped away the outer jacket - terminated with standard banana plugs from Radio Shack, so nothing special there. They lay nicely on the floor and run along the baseboard into the back of the credenza. Works for me.