I think the vocals are too aggressive for the instrumental during the rapped parts, they should be spoken more softly IMO. I would also double the vocals for the verses, but that's more of a personal preference and I don't think that would be necessary. The vocals I think should also be mixed more quietly since at this point you're probably just keeping these recordings (AKA they are too loud).
This song is pretty much a smooth jazz song with quick, palm muted guitars. Reminds me a little bit of some Dave Brubek mixed with the Spyro OST (Stewart Copeland) except without pianos. I get that you have a busy guitar riff going throughout the song, but it needs some improv or a solo to break it up and make it more interesting. Like, right after the first chorus you could put a busy solo there and after the end of the song you could easily jam a trumpet solo or keyboard solo while dropping most instruments except the palm muted guitar and light drums with a bass line that riffs off what the soloist plays. Man, after that you could finish on a big chorus or a drop out chorus. Like I feel the song has more potential.
As it is the whole song is a bit of a plateau. Yes, I hear your swells, but they are mixed/played in a way that the volume of the song isn't much affected, this is another reason to mix your vox quieter. It needs to be more dynamic.
I enjoy the sound you got here and your drum mix is really good with that hard hitting snare ( reminds me of this one song from the Trigun OST) Nothing sounds like it's badly EQed and I get the work you put into it. Keep it up.
(listened on headphones and some old 2003 emachine pc speakers)