A match EQ plugin would be super valuable for Direct Input acoustic instruments.
In effect, a match EQ analyses the frequency spectrym from two sound sources noting where they are different and creates EQing that causes one of the sources to sounds more like the other. They can be surprisingly good at making your direct pickup sounds more like a natural mic.
Logic has a great one:
I assume this was the approach Tone Dexter was planning on (though I don't know for sure):