AES / Cary Six Pac - upgrade suggestions

I am thinking about upgrading from my AES/Cary Six pac mono bloc amps. I use the AES DJH preamp. What would you suggest? I love the Cary line, I had a Cary SLI 80 prior to the Six pacs, and at that time I did not think it would be that much of a sonic up grade when I purchased the Six pacs, boy was I wrong! The Six pacs where a big up grade from the SLI 80. What would I have to go to to get a "big upgrade" in sound?