I'll echo another review I saw: Buy if you want to support the vision, wait if you want the game.

There is certainly a learning curve to Manor Lords, so if you're going in without much prior knowledge I think you'll get more content out of what's there right now. What is in the game generally works fantastically with the exception of a few minor gripes with pathing logic. There's an incredible amount of detail so it's clear to me what the dev's standard is he's holding himself to and it makes me feel this game is going to be legendary. With the way everything interconnects, I imagine every content update is going to expand replay-ability exponentially.