Hmm interesting sound you have here
I really love how this starts off, with some heavy guitar, and not just that its sharp and heavy sounding wich really fits well, its actually a good and kicking tune, something i could see in an action scene of a dramma, so awsome job here and would love to see more into this, The piano portion is also a nice touch aswell, i like what you did here with the two mixes, that was a pretty good idea, and wouldnt mind hearing more tunes like this, anyways nice work here nice quality.
~~THINGS TO IMPROVE ON~~
How to improve on something thats already good, you have a great idea here, the trembling in the guitar version was probably not needed, other then that this was a pretty good piece.