Hey Steve,
Congrats on your next challenge. :)
I don't know how widespread my opinion is, so I wouldn't base decisions on it. Instead, if this were my property, I'd pull comps to get the names of listing agents who have sold historic houses in the vicinity and I'd take a couple of them out to lunch and pick their brains to learn what buyers expect in this neighborhood.
My comps would go back a couple years and include Active comps since my goal would be to see which listing agents are most active in the neighborhood. The ones with the most listings are the ones I'd want to talk to. If that didn't work, I'd drive around looking at For Sale signs, call and ask how many historic sales each agent has under their belt, and take a couple of the experienced ones out to lunch.
If this suggestion proves to be of value, I wouldn't mind a tour of the property when it's ready to hit the market. :) It sounds interesting. Drop me a line.
Good luck!
David