What a great looking entertainment center!
Will be interested to hear what Danny sayes about the A/V-3s across the front as I currently have the box built and about to order one for my center while undecided about the L/R (probably A/V-1 on stands due to my future plans - wall to fireplace to wall split enterainment center )- rule out the A/V-3 and A/V-O floorstanders. A/V-2 and A/V-3s atr possibilities. But that is the subject of a future post as I am not going to hijack you thread.
The A/V-0 on the front may create a problem that hopefully Danny will adress. Specifically, how will the entertainment center 'wall' impact the omnidirectional sound radiation? If adverse, how about the similar size A/V-3 with the transmission line reversed for forward porting? True, less base - but you do have a sub. Also, with the sub, may not need to reverse the transmission line, retaining rear porting with less than optimal placement.
A/V-3s replacing the Klipsh would be appropriate with their accoustic design and decent 6-8 ohm load. While I saw your post on AVS prior to this I didn't post there. My frustration with the lack of DIY MTM designs above 4 ohms keeps bringing me back to GR Research for a matched set. Note, the A/V-3s will sound significantly different than the Klisph. Personally, I have found horn tweeters, while very precise are also very forward and 'in your face.'
A suggestion to think on in the future - particurally when replacing receiver. I don't know what cooling you have - ventilation and fan exhaust to the rear? You may want to replace the glass front. Go into Best Buy (Magnolia Center)and look at their Salamander units. Instead of glass, notice the perferated aluminum sheets - that can be painted to match the stain of your entertainment center. When I design/build my center, that is what I will use front (and probably rear) for great ventilation and looks while retaining remote control functions. Just a suggestions.