I would love to listen to what you have, bet it is awesome. I have a Cas2 that I love. Have listened to lots of Klipsch and love the sound. Here's my thoughts on amps and speakers. Different amp, same speakers, different sound. Vice versa and so forth. Look for the marriage. There is something very sweet with the Threshold that is almost tube like, but tube like, isn't tube. Threshold, beautiful class a sound that has wonderful highs, mids and lows. Perhaps, more definition than tubes but extremely musical. The thing about tubes though is that gentle tuck and pat it gives you with the bass and how it sweetens the highs and mids. With some Sonus Faber Concertos, I have been swapping the Cas2 in for a Audio Research tube amp and both are wonderful. Which is better? Depends on the piece of music and what you are looking for. Both give unbelievable listening pleasure, that is very different. I have been listening to the Audio Research for a while and am missing the Threshold. That said, the Audio Research is great and has earned its time.
I would have to have both of them and swap them in and out. I believe you will find that if you were to perhaps move out of the Threshold and go to the Manley there will be something missing in some of your music.
Gotta mention, with the Cornwall, incredible efficiency. I run some Altec Lansing VOT's with 6 watts/channel of SET sound that is a total wow factor.
That said, if you listen to something that blows something else completely out of the water, you have gotta go that direction. Trust your ears and not other's opinions.