i've been working on structural columns in desertopia. they hold up the roof and the mob factory. total pumpkin expenditure is estimated to be 20,000
as a bonus, the columns are large enough that one can live inside. yes, desertopian tower apartments.
i also went and checked my pumpkin farm, i've saturated my chests with 450,000 pumpkins and enough slices for 85000 melons.