Still considering various options for thickness of wood for different projects and parts of them, and at this point I'm onto considering their weight......aside from the tool cady cube, duck board & chicken pen, the least square footage item on my list is the ladder, which will be about 110lbs.
*All the wood species I'm planning on using are about 45lbs/cubic foot so the variable is indeed just thickness (& weight to be carried) not species.
I don't think I really need to have the same thickness of wood to hold me up (ladder), with the same span as 8 charger plates...the plates I strongly suspect will be fine at 1/2, maybe 1/4th the thickness...