I would probably want to use a tube amp with Klipsch Heritage speakers including Heresy.
Whereas with the original OHMs the key would be throw power and current at them for best results. Class D amps are a natural for those.
I purchased a pair of Cornwall IIIs a few years ago. I used a PrimaLuna One Integrated with them and thought the two worked well together.
I had them in a dedicated room so I could play them loud enough to sound good. My room was a lot smaller than yours; I had them placed in the corners toed into my listening chair. I tried a Bel Canto class D with them and the bass was a ton better but I found the sound too dry and sterile. The PrimLuna integrated was very nice for the $$ and dead quiet.
I only purchased the CWIII because I had a pair of Forte IIs and was hoping they would be a big step up in sound. Based on the cost, I much preferred the Fortes and the CWIIIs were just too big for my room anyway. The Forte III might be a much better choice for you assuming you do like the Klipsch Heritage sound (e.g. stands not needed, better bass, great looks, ...).
Good Luck...