As you note, it’s difficult to get iron of the world market. Wood construction sectors are not efficient, and there also really isn’t enough wood on the market either.
I disagree. there is plenty of cheap wood available in 1836 on the world market. And while wood construction sectors are less effecient by a certain degree" all else (notably prices) being equal" the degree by which it is less effecient isnt always that big no'r are circumstances of a nature of "all else being equal" when wood is cheap in 1836 and iron and tools are expensive or alternatively hard to get.
The "nominal" material cost for wood construction is 1000£ for 1 construction point, for iron construction sectors this is 720£ per construction point. So it's about 30% cheaper, but not when wood and cloth is -20% below market price and iron is +20% above market price. 20% more expensive tools and iron would push the price of an iron construction sector to 820£ per construction point and -20% input prices would push wood construction to 800£ per construction point.
Labor cost and availabillety has to be taken in mind too, as well as gainfull employment. The Netherlands would logically move away relatively soon from wood construction given it isnt all that manpower rich, (like say 15/20 years into the game) for other country's that have loads of people and even unemployment wood construction actually provides far more jobs per construction point which has its own niche utillity.
Even on a matter of "early prepping of the construction industry", a big consideration should be made where you stand in mining tech too, and afaik the Netherlands start with good tech but not great mining tech so there is a degree to which expansion into iron mining would have diminished returns. This matter of diminished returns could bite extra hard when one has the alternative to produce wood and cloth at high throughput rates very early in the game as the output bonus of throughput can mean a fair bit in how few plantations or forrestries you'd need to feed "a growing construction sector" (one which has to invest construction points to build construction points) with cheap wood and cloth.
In certain countries where high troughput is easily attainable, like Russia for example, you have to contemplate that each forrestry that nominally might only produce 60 wood with sawmills could produce 120 wood per level with 100 throughput which then again wouldnt even be that hard or uninterresting for Russia to achieve given how great her wood resources are at base. In a sense of building up enough supply to a construction sector that your building up, you might be that Russia that with each level of forrestry can provide enough wood for 1.6 construction points for roughly 200 construction points invested , whereas if you were working with iron construction sectors and "picks and shovels" as your mining PM (aka you havnt even got atmospheric engines yet) then you need 2.5 mines to feed 5 construction points (besides the tools and the other materials) which is about 0.8 iron mines for the same 1.6 construction points the forrestry provided in my example for a construction cost of 400 construction points. Which is basically a mathematical argument that says that under circumstances its cheaper to build up the relevant industry and feed the resources for an equivelant amount of construction points trough "outdated wood construction" than it would be with iron, and this logic permutates to following "better construction methods" for the construction industry.
A Russia that would do this would likely mostly do it as a means to fill the gap in between attaining effecient enough tech to make iron construction worth it, which could be relatively soon for Russia but having used wood construction for a decade or so could easily be a perfectly viable choice for it. Picks and shovels arnt effecient as a means to get iron, atmospheric engiens are better but then again condensing engine pump an dynamite isnt that far down the line either and thus "even better, les deminished returns on your inron investment" but it all costs tech investment that could be directed elsewhere. Once it would start to convert to ion construction from wood construction such a nation would be left with an excess of domestic wood and cloth production which however is usefull if you invest relatively soon in clothes and furniture and it wouldnt be a dumb choice as Russia to make something like furniture a specialty. In a way thats a bit of a mater how you stimulate the emergence of an industry at a specific point of time and make best use of it even as circumstances change, the point that is rather relevant int his to the Netherlands is that while Indonesia is neither great really as to produce loads of minerals that it can feed a lot of wood and cloth to the Netherlands at cheap prices in part due to its low labor cost, thus its fairly easy to attain or stimulate the expansion of fairly cheap and productive wood and cloth out of the colony that can serve first these wood construction sectors and then finished good factories in Holland.
