In Manor Lords, development upgrades offer significant benefits, but they are limited and permanent. To get the most out of your settlements, prioritize upgrades that enhance farming, trade, gathering, and industry. Some key upgrades to invest in first include the Heavy Plow for faster farming, Charcoal Burning for efficient fuel preparation, Deep Mining for endless ore resources, Sheepbreeding for infinite materials and income, and Better Deals for advantageous trading.