I think it's very difficult, It should be more balanced. Also, it would benefit to have some sound effects, as it makes it more engaging. Moreover, it should be clearer that enemies fuse, I didn't know what was happening with them. Also, at the beggining of the game, it' isn't clear where you have to put the buildings or the creatures.
Pero vamos, que mucho animo, puede mejorar bastante con unos pequeños retoque y mejoras visuales. Si lo actualizas estaré encantado de volver a probarlo