if you are not going to have the singer sing, then you need to start changing up the tone more then just adding a sax
Also definitely look into bringing the voice out more, instead of just a monotone volume, a voice is not at all monotone, it has emotion and feeling, not just a single volume,
Think about how people throw rhymes on stage, they hold the mic at varying distances from them and then bring it close to emphasize words or a feeling, push it away when they want people to only see them for what they.. As a person, are doing... To be big or small or looking for a triumph at the end of their beat.
That's the fault of the audio tracks that are in the file format for download...
They have no emotion and can really detract from a song if you are not careful
look into a voice actor that can rap along with you, would love to hear a different track for the voice in this song