It feels a little bit like cheating in Manor Lords, but the development upgrades you can get can do some powerful things to improve your settlement. However, to balance things out, the development points you need to unlock these enhancements are given out very sparingly. In fact, you won't get even close to the amount needed to unlock everything on the sphere grid. To make matters even more stressful, there's no way to undo a choice you make, so any point spent in error is locked in until you start a new game. There's none that can make your game harder, but if you pick one that offers no benefit to your current settlement or goals, it might as well be a negative in terms of the opportunity cost. For the best experience, here are the developments you should invest in first.
How to get development points
Before you can spend any development points in Manor Lords, you have to earn them. This is a slightly obfuscated system that you may not fully understand if you're not paying close attention, but it does make sense once you know what's going on. Development points are tied to you reaching new settlement levels. You can incrementally grow to a small village, a medium village, a large village, a small town, a medium town, and -- finally -- a large town. Each one requires a larger number of burgage plots and for you to upgrade more of them to higher levels. In any one settlement, you can earn six development points.
Best developments to get first
The development tree is broken down into four segments: farming, trade, gathering, and industry. Here are some of the best ones you can unlock early.
Heavy Plow
No settlement can survive only on hunting and foraging for food. Farming is the only way to make sure your storehouses are well stocked with food, but even a fully staffed farm is painfully slow to harvest. The Heavy Plow upgrade adds a plowing station to your farms so you can make use of an ox to not only make plowing your fields far faster, but also tospeed up transporting your crops to the storehouse.
Charcoal Burning
Preparing for winter is your primary concern for your first year, if not the first two, in Manor Lords. Lack of food is one thing, but if you run out of fuel to keep your population warm, they won't last long. Firewood is your basic form of fuel, but it is very inefficient. This development lets you build a charcoal kiln that gives you two charcoal for every one firewood you feed into it. That will double your potential fuel reserves in a snap.
Deep Mining
All natural resources will eventually run dry. While you can regrow trees and let berries regrow, ore deposits only have so much material for you to mine before they're tapped out. You can break the laws of nature with the Deep Mining development that lets you upgrade any mine into a deep mine that somehow never runs out of ore. This only works on the slightly rare rich deposits, but is still incredibly powerful to have an unending source of ore to build or sell.
Sheepbreeding
Speaking of getting an unending source of materials and money, Sheepbreeding makes something that you would expect to happen, but by default does not, actually occur. If you have a sheep farm, those sheep will be completely uninterested in mating and having more sheep babies. Snag this development to let nature take its course and get yourself an infinite supply of sheep for materials and to trade for quite a high price.
Better Deals
And while you're trading, unlock better deals to keep from getting ripped off. There's a tariff on anything you import in Manor Lords of 10 regional wealth, but this perk waives that annoying fee. Since you never quite know what resources you will have and what you will need to import to build your next structure or upgrade, importing is essential for reaching the late game. The earlier you invest in this, the more you'll save in the long run.