The idea seems good though. By occupying land you are hoarding scarce resource. Tax should incentivise you to occupy less. I think the tax should be progressive so if you have small house and lot you don't owe state that much but if you have McMansion you should pay handsomely or sell it tho someone who can actually afford it or to someone who splits the lot between multiple buyers.
Some large percentage of land value taxes could be dedicated to improving transport infrastructure around the place where high taxes come to lessen the squash.
