I've no familiarity with current NAD products. Those I owned were excellent values. "Class D" always sounded a bit like snake oil to me. The data seems to show it.
As to tubes sucking up power, I recently installed a vintage Sophia EL 34-based amp (35/channel) and noticed no change in my electric bill. Remember to trn off the exhaust fan when you leave the bathroom.
Had I the $ I'd have bought this: https://www.primaluna-usa.com/primaluna-evo-100-tube-power-amplifier or, since I know an excellent tech, this: https://www.amazon.com/Willsenton-R8-Integrated-Amplifier-Headphone/dp/B08133TH98/ref=sr_1_3?hvadid=604661045408&hvdev=c&hvlocphy=9007539&hvnetw=g&hvqmt=e&hvrand=5062205048887958487&hvtargid=kwd-1326307720789&hydadcr=14359_13354852&keywords=willsenton+r8+tube+amplifier&qid=1687221053&sr=8-3&ufe=app_do%3Aamzn1.fos.765d4786-5719-48b9-b588-eab9385652d5