Since in 0.9 it generally takes quite a lot longer to get large amounts of building material, if one wishes to build a lot they need quite a sizeable chunk of their colony dedicated to this task. Why is this an issue? To put it simply, it strongly disincentives building. Will that stop people building? Not at all. But it will make their lives a lot harder as a result, which seems wrong to me; I don’t feel like creative expression should have much impact on the balance of the game.
Outside of late game, the game becomes actively a lot harder while you’re mass producing blocks, and a lot easier while you’re not, which I think is a pretty crucial factor. You could double your guard force if you built minimalisticly. I’m not sure how much block production the game is balanced around, but it does become way easier if you don’t dedicate much to it.