I personally would suggest adding a moisture meter to the list of tools. The Electrophysics CT-33 is used by many surveyors, and can be found for as little as around $170 (new) on line (there is a specific "marine" version of the meter which is exactly the same except for color, and for $100 more).
I appreciate the difficulties in trying to determine an absolute moisture level in a core, especially for an amateur like me, and particularly in the hull. But, I found my moisture meter to be very useful in evaluating the condition of the decks and cabin structure regarding general moisture penetration qualitatively, not quantitatively (after being given some education by a surveyor).
In my own going over of boats, I found that the moisture meter was usually an 'absolute' indicator, which is what I was looking for. On most of the boats I looked at, either the meter showed low levels of moisture (low single digit percentages, barely tickling the meter), or it was pinned to the end of the scale. I found very few cases of in between (except at the margins of moisture-laden areas).
I found it very useful, if in going over areas of deck or superstructure, the meter showed low levels, and then jumped to the extreme (such as around hardware). I don't know what the actual % moisture level was in those cases, but to me, a pinned moisture meter reading was probably not a sign of something good. I used it to 'rule out' boats that had extensive areas of moisture, which for me was a deal killer (and saved $1000 on a survey for boats that passed the first step).
Good luck, and happy hunting!