Wood is the fastest source of resource in game. But age advancing cost wood sounds like a trade off rather than a bonus to me. 800 wood for advancing to imp is really really hard and even stockpiling 400 wood is also not that easy.
Funny how you still can continue playing with trash units even after gold runs out but it is completely over once you run out of wood or loss access to it. Don’t get me wrong. I’m not disagreeing with gold being most valuable resource in most of the practical cases. But theoretically it is wood.
I think until imp food is the most important and valueable ressource.
In imp this changes to gold just because even if you have still a lot remaining it’s often hard to generate the income.
YOu can also make an argument that throughout the mid to lategame stone is in most cases more valueable, but not necessarily also the generally most important ressource.
And the problem with when wood is scarce it generally means there are no res left. So if wood is scarce there is usually also no gold. So this kind of comparison is weird. I think I never had a game where there was no wood anymore but lots of gold left. It just doesn’t happen.