hmmm
This song has alot of potential but a few things need alot of work.
Firstly what are you using to record your midi?
Would you try using a composition program such as FL studio yto help use the midi chanels with more smoother instruments.
and i guess the best advice I could give would be in the form of two words.
Clipping
and
Quantising.
Clipping: Is the term used for audio that is distorting. you know how on most programs theres a volume level indicator? well when the volume levels go into the red (Orange in a few programs cases) it means that the sound or sounds are distorting or wont sound the same once you export the song.
Quantising: simply is timing. The song isnt in time, and it is very evident at the beginning of the song.
but yes, apart from those few things the song itself is great! keep it up bud.