I really like what you've done, it's a very clever way of interpreting the song just by changing the tempo.
It makes it feel very anthemic, like it's the theme to some sci-fi movie. I do feel you could capitalise on this by utilising more changes in dynamics.
Overall I find it's quite loud enough as it is (you'll wanna watch out for a couple volume spikes here and there in fact), you're just missing some quiet parts.
Well done nonetheless.