Done! I appreciate all the feedback guys. I had been leaning towards #1 at first...but FAR more people liked #3. Plus my sweetie liked that one the best.
And now that it's in the build...I think it looks fantastic. Pidoma....thanks for the suggestion...and thank you to everyone for helping me with your opinions.
The extension was actually fairly quick to make. Took maybe 2 hours at the most. I took lots longer than that playing with color combinations.
I made it a 14 inch extension...which is probably longer than most...but I wanted it to wrap all the way around the motherboard tray, and then make the turn to be facing the PSU's with the connector. So it makes a 270 degree turn. I asked some questions in the sleeving thread about how much shorter to make the inner row of cabling so that the extension will hold its shape nicely....and Wisk and Furion92 were kind enough to supply me with the formula you would use to determine length delta. You can find it over in the Sleeving FAQ thread...or I'll give you the simple version here. As long as you are using the standard 24pin connector...you are going to have about 1/4 inch of difference in the inner row for every 90 degree of turn you want in your extension. So...if you wanted to make a perfect half circle extension....your inner row would need to be about 1/2 inch shorter than the outer row. Mine is making a 270 degree turn, so my inner row cables are 3/4 inch shorter than the outer row. And it works perfectly.
I put a few cable clips on it for now. I'm still planning on doing some cable sewing, but it will be one of the last things I do. It will keep the pattern a little tighter...but it holds pretty well the way it is now. I decided to use 16 awg wire for the extension so that the cabling would be a little thicker and the extension would be relatively stiff. I think it worked well. I'll probably use 18 awg for most of the rest of the 24 pin cable on the back side.
I'm still dreading the 24 pin cabling that the extension plugs into. Not nearly as easy as this was. The other part will have all of the double wire sleeving jobs to do, and I'll be adding some wires to start the 2nd PSU automatically, as well as a break wire to the Aquaero so that it can shut down the PC on an alarm trigger. But I don't feel like I need to do that before the waterblocks. With this extension done, my list of things I'm going to do before putting on all the waterblocks is getting pretty short. But I do need to grab some temperature data at different overclock levels while its still on air. I want to know what the improvement is when I go to water. Might play with some of that today.