At the top of the map, it feels weird to have bushes in an area you can't access. Since the main functionality of bushes is to encounter wild Pokémon, people could misinterpret it as being an area you're supposed to access, perhaps later. Maybe you have some other grassy looking tiles you could fill that area with instead.
You should probably also put something in the area to the left of (what I presume is) the lab at the top, or just block it off completely.
A good rule of thumb is to try and refrain from making dead ends and areas that don't serve any purpose. Sure, you'll be able to see the garden behind if you go there, but if you really want that area to be accessible you should 1. make the entrance to the area wider, and 2. put something interesting there, like a bench with an NPC or something.
That's a lot of logs in front of the lab. You could reduce the amount of logs, and if you want to prevent the player from going on the right side of the lab, it could be better to just make the cliff one tile to the left so there is no grass on the right side of the lab.
The path down to the Poké Center is maybe a little bit long. Another rule of thumb is that the player should (almost) always be able to tell where to go, without having to run around a huge map searching.
If the player is standing in the middle of the map, above the lake, it'd be nice if they could see a little bit of the Poké Center roof, so they don't have to turn around if they went the wrong way.
Other than that, it's really good! There are some small nitpicks, like the area with the market tent being a little claustrophobic, and the area outside the big house on the left being a little small above the staircase, but that's mostly just my prefrence I guess. Hope this helps!