I think there is great value in the NR7100 or the cousin LX305 but to take advantage of the excellent Dirac and base management, best to spend another $200 and use a Wiim + a clean sounding DAC to it. So for under $800 you still get an excellent sounding 2.1 amp with Dirac room correction.
You can't use Dirac without internal DAC. If I understand correctly, you propose this configuration:
streamer -> external DAC ->analog input -> internal ADC -> DSP with Dirac -> internal DAC -> amplifier
While you dislike this version:
streamer (external or internal) -> digital input -> DSP with Dirac -> internal DAC -> amplifier
IMHO first configuration is not optimal.