I think, that this is an interesting concept, but the tutorial should be more interactive, pixel art really shouldn't be stretched in the way it is here, the player/ground/lava does not fit in with the style of the blocks (there are lots of mixels), the spiky blocks should maybe also hurt the player. You should maybe also give the player some animations and add some more polish to the game overall.
Also if you are trying to get it on the google play store, like you said in your post, how are you going to make it mobile compatible, you have to use WASD to move and clicking is already for dragging blocks, so that would probably be hard to make mobile friendly.
I do really like having a map though.