Hi gene,
DAWs are certainly very capable, but typically they cannot compete with a dedicated mixer in terms of latency. In your configuration you would have A/D D/A latency from the GLD, Dante transport and virtual soundcard latency, and the DAW latency which, depending on plugins, can be of several ms. Overall roundtrip latency could well be in the 10s of ms. While this wouldn’t matter at all for streaming / broadcast / recording purposes, it can be an issue for FOH and even more so for monitors. Other than ease of access, it’s the main reason DAWs are seldom used for live mixing (with some notable exceptions that run on dedicated hardware).
As for using GLD as a controller, you can certainly set up some MIDI faders in GLD and run our A&H MIDI Control driver to simulate a HUI/Mackie Control surface (as far as track level, mutes and solos are concerned) or to map individual controls, but again not sure you can easily replicate the immediacy of monitor sends-on-faders. Certainly worth experimenting though.
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