Hi John,
I am the Odyssey Audio Singapore dealer.

I just finished enjoying a session with the khartago. Companion components are as follows:
Epos 14 speakers
Bryston BP20 preamp
Musical Fidelity 624 CDP
Mixture of Siltech, Groneberg and Kimber cables.
My entire Odyssey setup is at the showroom...wish I could bring them back home...

Anyway...Price-wise, none of the other components are cheaper than the Khartago. But honestly, this 'budget' amp is very much at home with them. I just finished the entire James Taylor 'Greatest Hits' CD. Man...I tell you, I really enjoyed the session. I forgot about listening to the system cos I was enjoying song after song after song...
IMHO, the khartago would probably bring your 780SE close to its optimum. I don't think the Etesian and Khartago would be 'too-good' for the other components. The khartago would simply bring the best out of them. And don't even think of comparing your CA amp with the khartago + Etesian. It's like comparing a Hyundai with an Alfa.
Well...the only down-side is...you might end up looking for better speakers. The Epiphonys would definitely be an option.
Oh....btw, just for kicks...I hooked up the Epiphony with a Mono pair last weekend. Obvious overkill... but boy oh boy oh boy...
Alex