Indeed, this song could use some mixing. I'm not too sure if the muffled sounds are part of the dark techno theme, but you could cut some of the lower frequencies to make room for louder melodic instruments. Some delay/reverb can also be used to give it a nice echo-ey feel.
This song feels very in-between atmospheric and energetic; if that's what you want, good! If not, removing some of the secondary percussion (anything that does not play on a downbeat) can make it more atmospheric, while enhancing the timbres of the instruments and implementing a melody or even some kind of melodic hook makes it more energetic.
Hope this helps :)