I like the start you have going on this. Since the title says "early" I'm guessing started with mainly wood and stone brick, because of how early it is. I'm not certain if you want to focus on playthrough or on building, but I'll assume building, since you've posted here ^.^ To build off of what
@Pellaeon and
@Bauroth are saying, I'd suggest going out into the world, and gathering a wider variety of building materials and furniture. The shape of the building is fun, but it feels bland at the moment (I know it's a WiP).
Personally, I'd throw background walls on the outside, to make it look like the tower is built within a fence (I'm not sure if that makes any sense). I would also change up the materials a bit. For example, make the roof of the tower a different material/color than the walls of that tower. As Pellaeon said, you should definitely add windows.
Fantastic start, though! It'll be interesting to see where you go from here
On a side note, I'd like to point out that most of the saplings to the left of the base will not grow into trees. Correct me if I'm mistaken, but I believe a sapling requires one open block to either side of it (you need an empty space on either side of the sapling), because when they grow into trees, the tree may or may not have the trunk extend one block to the left or right (or both). So, having saplings bunched up like that, with torches, means most of them will never grow. If you wanted them like this, and just wanted a sapling garden, then you can ignore this comment!