I would agree with you assessment. Though I am not a huge Krell fan, I've always thought their best work was in the very early 90's. I thought their KAS and KSA 150/250 were some of the best amps they've ever made.
I found that the FPB series, though a bit more transparent, lost that 'organic' musicality that I prefer.
The quest for more transparency has been the downfall of many designers though, not just Krell, IMHO.
John