As a fellow VA owner, may I say you have a great pair of speakers Manicaudio. I also know that VA's can really suck up the power and thrive on it. I had a Pio Elite SC-25, very similar ICE amps as in your SC-07, and found that it was strained when pushing my 4 Ohm Viennas. I added a Parasound 5125 and no problems whatsoever. Basically I can get as loud as I please and no strain on the amp. It never breaks a sweat. And that is comforting for me to know.
The above being said, I assume you are looking for a 2 channel integrated amp to incorporate into your existing multi-channel HT system? Therefore whatever integrated amp you choose should have an HT Bypass feateure for seamless integration. I do not believe the MA6600 has this feature. There are many, many other makes and models to choose from that will improve your 2 channel performance for music and adequately power the VA's for either 2 channel or HT applications. So I am curious why the McIntosh 6600 at 6K? I could think of 1/2 dozen models at 1/2 the cost of the MAC that will get the job done with your VA's and have an HT Bypass feature
Don't get me wrong - I agree with the route you are pursuing. You need more power to make the Beethovens really sing and a quality integrated amp will do the trick. I am just wondering why the MAC when there are a lot of other high quality options. Two that immediately come to mind that would rival the McIntosh are the Musical Fidelity M6I (3K) and Marantz PM11S2 (4K). They just don't have the blue power meters.
Marantz PM15S2 LE, Oppo BDP-103, Simaudio Moon 100D DAC
VPI Traveler V2 with an Ortofon Rondo Blue and Simaudio Moon 110LP, Technics SL-1400 with an Audio Technica AT-14sa and Pro-ject Phono Box S
Dynaudio Focus 260's, Rel T-1 and a Panasonic TC-P54S1.