Tather than having all harvested wood be of type "wood", I propose that it be defined by the type of tree from which it was harvested. This would apply to the non-common trees, but all Palms would fall into that single category.
Where a building calls for "Wood" or "Boards", any type may be used.
In a Wood Treatment Tank, however, each type would have it's own baseline statistics, making different types of wood more or less suitable for achieving a specific set of characteristics.
The primary impact of this change would be to increase the number of inventory lines used by wood and boards. With relation to treated boards, it would in general make some small projects slightly easier - successfully gathering 12,000 Pratyeka wood, for instance, is highly unlikely to be worth the effort for the processing work saved by their starting characteristics. A third effect is that it makes possible as a new building requirement boards from a specific type of tree. While I would consider this most appropriate foe Test or decorative buildings, the possibility does exist that it could be used elsewhere.