Here i will show you what i mean about the terrain, what is missing and show some bugs.
If you look on the pictures i have attached you will see why it is 1/5.
Picture 1: As you can see, no tile variation, no doodads, just tree spam and some deletes, i suggest you add some doodads, and make tile variations.
Picture 2: The walls looks ugly like that, you should change their variation to "2" then they will all look the same. Also the doodads right to the hero, why are they there? They look ugly, i think you should make some icy spikes around the cliffs.
Picture 3: Here is a bug, the units never attack the towers because you placed them to close to each other, this is a terrible bug, i suggest you put only a single tower and remove those doodads around it.
Picture 4: You must do something about where the players can choose their heroes, place the terrain and wisps in a unused corner, it looks terrible there.